model of molecule web viewthe motion of the particles and the strength of _____ between the...

Science 7 Mrs. Clement

Unit 2 Chemistry: States of Matter

What You Will Learn:

The behaviour of matter can be explained using the particle model.

Matter is anything that has mass and takes up space

The four states of matter are solid, liquid, gases, and plasma

Matter is made up of molecules that are in constant motion

Mass is the amount of matter present. It remains constant.

The metric basic unit of measure for mass is the gram.

Volume is how much space something takes up. The metric unit of measure for volume is the liter.

Density is the relationship between mass and volume

Why chemistry is AMAZING:

Properties of matter determine how different materials can be

Describing and measuring matter enables you to communicate your observations with others. You and all the materials and living things in the world are made

You eat, wear, breathe and use mixtures every day.Many mixtures, such as gold ore, contain important substances that people can extract using their knowledge of physical

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A Glance into the FuturePre-quiz check

inLesson Key

Words

HW Check

Post-unit check in

2.1 The Four States Intro to solids, liquids, gases Phases of matter Tech Connect: Plasma HW States of matter

PropertySolidLiquidGasTemperatureMelting pointBoiling point

p. 9-11

2.2 The Structures of Matter LAB #2: Particle Model &

table HW: Particle Models

Physical changeModelParticle model

P. 13-14

2.3 Physical Properties Physical properties table Q&A Analysis & Evaluation HW: volume and density

VolumeDensitySolubilityMeniscus

p.18

2.4 Mass vs. Weight Measuring mass and weight LAB 4a Density Tower Lab 4b Density Blocks HW: Density Q&A

Massweight

p. 37-38

2.5 Understanding solids, liquids and gases

More in depth look at solids, liquids and gases

Table HW: solids, liquids and gases

CapillaryElasticityAdhesionCohesion

p. 44-43

Unit Review & Quiz

Recap Key words

p.45

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2.1 The Four States of Matter(Textbook p. 107)

Matter: ___________________________________________________

Matter is anything that has _____________ (takes up space) and has a _____________ (contains a certain amount of material). Matter doesn’t have to be visible (even air is matter). All matter is made up of _____________ that are constantly moving. The motion of the particles and the strength of _____________ between the particles determines a material’s state of matter. Some characteristics of matter that can be observed with your senses are _____________, _____________, _____________, _____________ and _____________.

There are three familiar __________________________: solid, liquid, and gas. Plasma is a fourth state of matter that only occurs at extremely high temperatures. Plasma is like a gas, but it can conduct electricity. It is found in stars, lightening, and neon lights.

States or Phases of Matter The three main states of matter are:

1. ____________________ An example is ___________________

2. ____________________ An example is ___________________

3. ____________________ An example is ___________________States of Matter:

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SolidsHave a definite shape and volume. This means that solids keep their shape and take up the same amount of space.

LiquidsHave a definite volume but no definite shape. Liquids will take the shape of the container in which they are placed.

GasesHave no definite volume or shape. The gases will expand to fill any container and will take the shape of the container.

PlasmaHas no definite shape or volume and is a highly energized gas. Plasma is common in the universe; it is not common on Earth.

States of Matter Cycle

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States of Matter in more detail: Write SOLID, LIQUID, or GAS in the table to match the diagrams.

State (Phase) of Matter MODEL OF MOLECULEPOSITIONS

Solids have a definite shape and volume.This means that solids ______________. and take up the same amount of space. Solids have a high cohesive force so the molecules of solids are packed __________. together. The cohesive force is the ____________________________.. Molecules are in constant motion; however, in solids, the molecules are ______________ you can’t see them move.Liquids have ___________________________. Liquids will take up the same amount of space but will ____________________________ in which they have been placed. At the molecular level, the liquids have a ____________________________, so the molecules of a liquid are spread far enough apart that they can flow over each other and ____________________________Gases have ____________________________. The cohesive force of gases is _______________ ______________, so the molecules are _________ ______________. The gases will ______________ ______________ ______________ and will take the shape of the container.Plasma has ___________________________ and is a __________________ gas. As with other gases, the cohesive force of plasma is _____________-______________, so the molecules are ____________________________. The gases will ______________________ and will take the shape of any container.

Due Date: _______________States of Matter

Fill in the blanks:

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1. Matter is everything that has ________________ and ______________________

2. There are four states of matter: ________________, ______________, _________________ and ________________.

3. _______________ is a fourth state of matter that only occurs at extremely high temperatures.

4. Plasma is like a ______________ and is found in stars, lightening and neon lights.

Data Table:5. Study the pictures and descriptions. Write the names of each

picture under the correct heading.

Ice Air Water Fish Milk Exhaust

a. Solids__________________________

b. Liquids________

___________

___

c. Gases___________

___________

6. True or False______ Matter is anything that is made up of volume and mass______ Solids can change their shape______ Liquids have no definite shape or volume______ Gases have no definite shape or volume______ Plasma is a highly energized gas

Read the following “Tech Connect” article to answer the following question in preparation for our next class.

Plasma: a gas that has electricity running through it. Plasma is sometimes considered to be a fourth

Tech Connect

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state of matter. It is found mainly in the stars and nebulas within our universe.

Plasma has fascinated people for thousands of years. The northern lights (aurora borealis) is an example of plasma in nature. In ancient times, the Inuit people believed that the northern lights were the torches of spirits guiding souls to a land of happiness and plenty.

Today you can find plasma in many manufactured items, such as fluorescent lights, neon signs, and plasma balls (as seen in the image above). The wonder that you experience when looking at a plasma ball is the wonder that ancient people experienced when looking at the northern lights.

Plasma can be used to cut and shape metal. Plasma cutters were developed almost 50 years ago, during WWII, to help speed up the process of cutting and welding metal together to build airplanes for war. Plasma cutters are now used to shape car frames, to cut large beams at constructions sites, and are even used by artists to cut and shape metal for sculptures.

Television screens are of the newest technologies that involve plasma. Plasma displays are not a new invention- research on plasma displays dates back a decade or more. It is only recently, however, that the technology has been developed to manufacture plasma displays at a lower cost.

So how does a plasma television screen work? A plasma screen is quite different from a normal screen. A plasma screen works by suspending an inert (inactive) gas, such as a neon or xenon, between two panes of transistor-covered glass that are meshed together. An electric charge is applied to the gas, turning it into plasma. This creates ultraviolet light, which illuminates phosphors that are built into the glass, creating light that you can see.

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Imagine it this way: the screen that you see is actually two glass plates that have gas (plasma) pumped between them. The space that the glass fills is like a teeny-weeny series of ice cube trays. Wires are strung along the top of the chambers, crisscrossing each other. Since the human eye cannot detect charged neon and xenon, the “ ice cube” cells are filled with red, blue and green chemicals (phosphorus). When the TV is turned on, an explosion of light is produced.

So, why do so many people wish to have plasma television? Plasma screens are ultra thin and produce vibrant colours.

2.2 The Structure of Matter(textbook p. 124)

This study of chemistry begins with an examination of ______________. There are two theories about the ______________ of matter: atomic and molecular. ________________________ states that matter is made up of atoms. ____________________________ states that matter is made up of molecules. Matter has been classified into states, or phases, of matter: solid, liquid, gas and plasma.

Particle Model of Matter

What is a model?

Why do scientists use models?

For more information, check out the following video: https://www.youtube.com/watch?v=VkeSI_B5Ljc

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https://www.youtube.com/watch?v=VkeSI_B5Ljc

Particle Model of Matter


The Five Key Points of the Particle Model

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Using the Particle Model

LAB #2 Particle Models of Matter

Getting StartedToday you will observe several simple demonstrations. By the end of these experiments, you should be able to explain your observations using the Particle Model of Matter

Driving Question: How can we model matter?

Hypothesis: _____________________________________ _______________________________________________

Procedure: Carry out the investigation. This includes gathering materials, following the steps and recording data.

Materials:- 2 balloons- 3x 30cm string- 1 pushpin- 1 meter stick- 2 pieces of tape

Procedure1. Tie one of the 30cm strings to the center of the meter stick2. Blow up both the balloons so that they are the same size3. Knot the balloons. Tie a string to each. Tape one balloon to each end of

the meter stick.4. Suspend the meter stick from the free string. Adjust the string so the

stick is evenly balanced and hangs horizontally. Pop one of the balloons with the pin.

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Draw sketches to show how the particle model explains the properties of a solid, a liquid, and a gas. For each state indicate the distance between particles, type of movement, and whether or not it has a fixed (definite) shape and volume.

State of

Matter

Sketch of Model

What is the relative distance between particles?

Are the particles moving?

(i.e. Vibrating,

rotating, or moving from

place to place?)

Does it have a fixed

shape?

Does it have a fixed volum

e?

Solid

Liquid

Gas

Due Date: _______________Molecular Models

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1. Use the Particle Model of Matter to describe (in words and pictures) each of the following:

the spacing between particles of a solid

the movement of particles in a gas

the movement of particles in a solid

the spacing and movement of the particles in a liquid

2. Imagine that the students in your class represent particles of matter and the school gym represents a container. Use labeled sketches to show how you would organize the students in the gym to demonstrate a change of state from solid to liquid.

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BONUS: $10 ClementBucks

Some scientists (mainly physicists) consider there to be two other states of matter that exist only at extreme temperatures: plasma and Bose-Einstein condensate. Use the Internet to find out about these two states.

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2.3 Physical Properties of Matter(Textbook p.108)

Physical properties of matter can be observed and measured without changing the chemical structure of the substance. The chart below lists some of the common physical properties of matter.

Fill in the blank boxes in the table.

Physical Properties Definition Example

Density

Ductility

Malleability

Boiling Point

Melting Point

Electrical Conductivity

Solubility

All matter can be detected and ______________. Physical properties of matter that can be measure include _________, ___________ and

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Meniscus


______________. Mass is the ______________ of ______________ and it remains constant. The metric base unit of measure for mass is the __________. Mass can be measured using a triple beam balance. Volume is how much space something takes up. The volume of regular shaped objects, such as a block of wood may be found ______________. Measure the object’s __________, __________ and ___________. Multiply the three measurements (LxWxH). The answer is labelled in cubic centimeters.

When measuring the volume of a liquid, a __________________ may be used. The basic unit for measurement is the ______________ (mL) for a liquid. When reading a graduated cylinder, the liquid has a tendency to cling to the sides of the container, creating a curve called a ______________. The tendency of unlike materials to be attracted to each other is called adhesion. When reading the volume, you must measure from the bottom of the curve.

The volume of an irregular object, such as a rock , can be found using a method called ______________. Water is added to a graduated cylinder and recorded. Once the volume of water has been recorded, the rock is added and the level of the water is recorded again. The ______________ between the first measurement and the second is the ______________ of the rock.

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Density is the relationship between the _____________________ of an object. The more ______________ the molecules, the greater the density of an object. By finding the mass and volume of the object, you can find the mathematical density. It can be calculated by ______________ the mass by the volume.

Example: Density = massvoume or = D=MV

Knowing the relationship of mass, volume, or density will help you determine whether an object will ______________ in a liquid. If the object’s density is greater than the density of the liquid it is in, the object will not sink.

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Due Date: _______________Volume and density Q&A

1. What is volume?

2. Liquids and gases are usually measured using the metric unit __________ and its prefixes, and solids are usually measured using _______________.

3. Estimate the volume of the following familiar objects and then compare with other students.

Can of pop _____mL measuring cup _____mL carton milk __ L ____ mL tablespoon(Tbsp) ____mL teaspoon(tsp) ____mL

4. The mathematical formula for the volume of a cube is _______________________

5. Volume is either directly or indirectly measured. Using a

graduated cylinder to measure a certain volume of liquid is an example of ___________ measurement. Another example of direct measurement is _____________________________________. An example of an indirect measurement is ___________________________________.

6. Draw a diagram of each piece of equipment you will be using.

Beaker Erlenmeyer Flask

Graduated Cylinder

Volumetric Flask

2.4 Measuring Mass and Weight

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In this investigation you will __________________________________________ of various objects, liquids, and dry chemicals. You will learn how to use the triple beam balance, electronic and spring scales.

Background: The difference between mass and weight is confusing because

on Earth, we are always in the presence of Earth’s gravity (9.8 N/kg). Everything has weight. We describe objects as being heavy or light.

The only time things can be weightless on Earth, is when they are falling freely and not supported by the Earth.

We usually find the weight of objects by using spring scales, such as a typical bathroom scale that you stand on. Gravity pulls on you towards the ground and causes the spring to compress, depending upon how much mass your body has.

A large body mass will be heavier than a small body mass. WEIGHT is how heavy an object is, and MASS is how much

substance or matter is in the object.

Now here’s the confusing part: Weight is suppose to be measured in Newtons (N), and mass in grams (g), kilograms (kg), or sometimes in pounds (lbs). We never talk about Newtons. Because we never leave Earth’s gravity to experience how different gravitational forces change our weight, we don’t need to distinguish between mass and weight. So, on Earth, we think of mass and weight as the same. Please remember though that they are not the same.

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MASS or WEIGHT?MASS: Mass is the amount of matter in an object , measured in grams (g) or kilograms (kg) etc. The non-metric system uses pounds for mass.

The mass of an object does not change if the gravitational force changes. For example, the mass of an astronaut is the same on earth as it is on the moon, even though the moon’s gravity is 6 times less.

WEIGHT: Weight is measured in Newtons (N), named after Sir Issac Newton. The weight of an object is dependent on gravity .

The weight on an object changes if the gravitational force changes. Weight = mass x gravity. A greater gravitational force pulling down on you makes you heavier. In outer space you are weightless.

For example: Comparison of a 80 kg astronaut. The astronaut has no weight in outer space, and is about 6 times heavier on earth than the moon.

Earth Moon Outer Space

Gravity = 9.8 N/kg

Gravity = 1.6 N/kg

Gravity = 0 N/kg

Mass = 80 kg Mass = 80 kg Mass = 80 kg

Wt = 80 x 9.8 Wt = 80 x 1.6 Wt = 80 x 0

Weight = 784 N Weight =128 N Weight = 0 N

When we use the term weight in our every day conversations to represent how heavy an object is we do not use the correct units of measurement. We should be using the units Newtons (N) instead of kilograms or pounds. However, because we do not travel to different gravitational force fields, which would affect our measurement of weight, the terms mass and weight can be used interchangeably on earth.

Practice:A hippopotamus has a mass of 1000 kg. Weight = mass x gravity

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What is the mass and weight of the hippo on earth?

Mass = _________kg weight = ________ x ________ = _______N

What is the mass and weight of the hippo on the moon?

Mass = _________kg weight = ________ x ________ = _______N

What is the mass and weight of the hippo in outer space?

Mass = _________kg weight = ________ x ________ = _______N

Object Mass (g ) Mass (kg) WeightSpring scale

Calculated weightWt = m x gWt = m x 10

One shoe

Pencil case

binder

Metric Conversion Practice

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10-3 10-2 10-1 100 101 102 103

SMALL LARGE


1.Label

the following on the metric number line below: metre, litre, gram,

kilo, centi, milli, deci, hecto, deca

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Prefix Symbol Valuemega M 106 = 1,000,000kilo k 103 = 1,000

hecto h 102 = 100deca da 101 = 10BASE Meter (m), Litre (L), Gram (g) 100 = 1deci d 10-1 = 0.1centi c 10-2 = 0.01milli m 10-3 = 0.001

micro µ 10-6 = 0.000,001


PROCEDURE:1. Work in groups of 3. Collect all materials and take them to a

work area.

LAB #4a Density Tower

In this investigation you will compare the density of a variety of liquids.

Viscosity is ____________________________________________

Density is _____________________________________________

Driving Question: Are some liquids denser than others?

Hypothesis: _____________________________________ _______________________________________________

Materials: 100 mL graduated cylinder, small 100mL beaker, glass stir rod, food colouring, petri-dish containing solid objects

Liquids: 20 ml each of vegetable oil, glycerin, yellow-coloured water, red-coloured isopropyl

Solids: paper clip, sliver of candle wax, plastic thumbtack, popcorn kernel, wood shaving

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2. Find mass of the 100mL beaker BEFORE adding a liquid MASS OF BEAKER = ________

3. Carefully pour 20 mL WATER into beaker and find mass BEAKER + LIQUID = _________

4. Calculate MASS OF (BEAKER + LIQUID) – MASS OF BEAKER = ___________ = mass 20 mL water

5. Record mass of water in the table below. The mass of the other liquids is done for you.

6. Use your fingers to feel the liquids. Describe their texture and relative viscosity in the table. Use as many qualitative descriptive words as possible.

7. Infer the relative densities based on touching and swirling the liquids. Record in the table.

8. Add ONE DROP of food colouring to the alcohol (red) and water (yellow).

9. Carefully pour the following 3 liquids into the graduated cylinder in the following order: GLYCERIN, VEGETABLE OIL, and WATER - do NOT pour in the alcohol

10. Let the liquids settle and then DRAW what you see in the diagram on the opposite page. Be as accurate as possible. Draw in the graduated cylinder measurements.

11. Carefully drop in ONE or TWO drops of green or blue food colouring and observe what happens.

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12. Following your teacher’s instructions, use a glass stirring rod to carefully pour in the ALCOHOL.

13. Add the alcohol to your drawing.

14. Now carefully add the solid objects one at a time, observing how they move through the liquids. Add the label the solid objects to your diagram.

Labeled Drawing of Density Tower (Use colour)

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Vegetable Oil

Glycerin Isopropyl Alcohol

(coloured red)

Water(coloured yellow)

QualitativeDescription

Relative Density(1=most;4=least)

Actual Density

D = m/V

m=18.4gV=20mLD=18.4/20D= 0.92 g/mL

m=26.4gV=20mLD=26.4/20D= 1.32 g/mL

m=16.2gV=20mLD=16.2/20D= 0.82 g/mL

m=20gV=20mLD=20/20D= 1.0 g/mL


Observations: 1. Which materials used are less dense than

water? Which are more dense than water?

LESS DENSE MORE DENSE

2. Which liquid has the most similar density to the food colouring? How do you know?

3. Are solids always more dense than liquids? What evidence supports your answer? __________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________

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4. Does the volume of an object determine its density? Explain your answer. ______________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________

5. Liquid A has the greatest mass of 200g and density 1.3 g/mL. Liquid B has a mass of 105 g and density 2.1 g/mL.

a) Which liquid will sink below the other? How do you know? ____________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________

b) Will the liquids sink or float in water? How do you know? ____________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________

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LAB #4b Density Blocks

In this activity, you will be comparing blocks of DIFFERENT DENSITIES. Each block has the SAME VOLUME as other blocks, but a DIFFERENT MASS.

Driving Question: Are some solids denser than others?

Hypothesis: _____________________________________ _______________________________________________

Materials: set of blocks

Procedure:1. Complete the first empty column in the table below. Decide whether

each block is made of metal, wood or plastic.2. Make your prediction as to whether or not a block will sink or float in a

beaker of water.3. Carefully slide each block into the beaker of water and record if it sinks

or floats.4. Complete the final column of the table after discussion with your

group.

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IN CLASS WORKTrue or False

1. Something that has a very low density has only a small amount of matter occupying a large amount of space. In other words, it has a low mass but a high volume. True or False

2. Density is a chemical property of matter. True or False

3. Density is a quantitative property of matter. True or False

4. Density is calculated by dividing the volume of matter by its mass. True or False

5. One gram of pure water occupies exactly 1.0 mL of volume. True or False

6. The density of pure water is 1.0 g/mL. True or False.

7. Anything with a density greater than 1.0 g/mL will sink in pure water. True or False

8. Something that is very dense has a lot of matter taking up a very small amount of space. True or False

9. The most appropriate unit for measuring the volume of your body is mL. True or False

10.In general, mL, L, kL are used to measure the volume of liquids and mm3, cm3, m3 are used to measure the volume of solids and gases. True or False

11. If you have 1000 cm3 of pure copper and 1000 cm3 of Styrofoam peanuts, which has the greater... mass? Explain how you know this true.

volume? Explain how you know this is true.

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density? Explain how you know this is true.

12. You have exactly 500 mL of each of four (4) different liquids labeled 1, 2, 3, and 4. Liquid 1 floats on 2, 2 floats on 3, and 3 floats on 4.

a) Draw a labeled diagram to show their relative densities.

b) Which liquid has the greatest mass? Explain how you know this is true.

c) Which liquid has the lowest density? Explain how you know this is true.

13. As you go down in depth in the ocean, the water temperature decreases and the salinity (amount of salt) increases. Which has the lower density...

a) salt water or fresh water? Use the Particle Model of Matter and a labeled diagram to explain your answer.

b) cold water or warm water? Use the Particle Model of Matter and a labeled diagram to explain your answer.

30

22 cm

9 cm

12 cm


c) cold salt water or warm fresh water? Use the Particle Model of Matter and a labeled diagram to explain your answer.

14. Which has greater density?

a) 1 mL of isopropyl alcohol or 1 litre of isopropyl alcohol?

b) A lead weight used for fishing salmon or a classroom full of chicken feathers?

15. Determine the density of the rectangular solid with a mass of 450 grams. You may use a calculator, but be sure to show your work and include your units!

16. An irregularly shaped piece of purple heart wood has a mass of 25 grams. Suppose that you place it in a graduated cylinder containing 35 mL of water. The water level rises to 37 mL. What is the density of the wood? You may use a calculator, but be sure to show your work and include your units!

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17. An object has a density of 200 g/mL. If the volume of the object measures 50 mL, what is its mass in grams? You may use a calculator, but be sure to show your work!

18. A rectangular solid made of metal has a density of 98 g/cm3, and a mass of 74 grams. What is the volume of the solid?

Fill in the table below.Symbol Base 10

ValueStandard

NumberValuemilli

m 10-3 1/1000 or 0.001centi

deci

metre

gram

Litre

deca

hecto

kilo

3. Fill in the table with the correct metric SYMBOLS.

MILLI CENTI DECI DECA HECTO KILOGRAM mg

METRE dam

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LITRE hL

METRE3 cm3

Density Blocks Activity

Density of pure WATER is 1 gram per milliliter (D= 1.0 g/mL)

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STEP 2: Procedure:

1. Each person in your group should HOLD a block in each hand and COMPARE the weight. As a group, determine which blocks FEEL

more/less dense than others.

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Block #

BLOCK Type of MATERIAL

(metal, plastic, wood)

PREDICTION(sink or float) in water

Actual(sink or float)

Is the block MORE

or LESS dense than

water?1

2

3

4

5

6

7

8

9

10


2. Complete the table below after you have inferred (educated guess) the relative (comparative) densities and lined them up on your desk from least dense to most.

3. Based on your sink/float data, where would you include water? Add water to the table.

4. Write the names of each block, and water, in a space in the table below.

RELATIVE (compare) densities of blocks, including water

Least Dense Most Dense

Procedure:

5. Now look back at the densities in the table on page 1 and fill in the table below.

ACTUAL densities of blocks AND water

Least Dense Most Dense

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Create a graph. Place the mass (g) of your objects on the y-axis. Place the volume (mL) of the object on the x-axis,

Density of Objects

Due Date: _______________Density Q&A

Volume (mL)

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Analyze and Evaluate:

1. Compare the ordering of blocks and water by densities in the two tables above. How accurate were you at inferring the densities by just feeling and comparing the weights? If you had trouble ordering a couple samples, do you know why they were tricky? Discuss. ______________________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________

2. Do all types of wood float in water? Support your statement with examples from your data. ___________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. How can you use sink/float data to determine if a substance is more or less dense than water? Support your statement with examples from your data. __________________________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________

4. Are solids always denser than liquids? Explain with an example from your data. __________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________

5. Use diagrams to model 2 blocks that have different densities (ie. one block is more dense than another). Use small circles to represent the particles in the block.

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6. In words, describe density _____________________________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________

7. Use a mathematical equation to explain density.

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2.5 Review Solids, Liquids and Gases

Solids, liquids and gases have definite characteristics. A solid has a ________________________. Solids resist being ____________ ____________. Another characteristic is ____________. Elasticity means that a solid can be bent or twisted a limited amount, and it will return to its former shape. A rubber band is a solid that can easily be stretched, and then it will return to its original shape and size. Some solids are also ____________, which means the solid can be formed into new shapes. Gold is a solid that can easily be hammered into a thin sheet.

A liquid has a definite ____________. but takes the __________ of the container holding it. When water is poured from one container into a container shaped differently, the water takes the shape of the new container. Other physical characteristics of liquids are _______________ and ________________. Adhesion is the attraction between unlike substances. When measuring liquid volume, your read the measurement from the bottom of the meniscus. The _________ is the ____________ formed because of the adhesion of liquid to the container. Liquids also have _______________. When a thin straw or glass tube is dipped in a liquid, the liquid will _________ _____________ in the straw or glass tube. This concept explains why coloured water seems to climb up a paper towel.

Water molecules are ________________________ because of a force called _______________. Cohesion is the attraction of like substances. As the molecules cling to each other, they form an invisible “skin” on the surface of the water, or what scientists call

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________________________. Surface tension helps a drop of water hold its shape, to hang on to itself, and to stack up on a surface. It also helps some insects walk on the surface of water.

When you pour a liquid from one container to another, the liquid takes ________________________. The molecules of liquids are spread far enough apart they can flow over each other and more freely than in a solid. Some liquids flow more freely than others. A liquids resistance to flow is known as the liquid’s ____________. The slower a liquid flows, the higher the viscosity. Honey has a high viscosity, while water has a low viscosity.

Scientists describe fluids as any material that doesn’t maintain definite shape. Both liquids and gases are fluids. The molecules that make up these fluids do exert a pressure on surfaces with which they come in contact.

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Characteristics of fluids:Fluids move from one area of high pressure to one of low pressure.

Example. When you suck air out of the top of a straw, you reduce the air pressure at the top of the straw. Normal atmospheric pressure then forces liquid from your drink up the straw to your lips.

Gravity pulls on fluids. Pressure in any contained quantity of fluid will increase with depth.

Example. When holes are places in a container, water will squirt out farthest from the hole nearest the bottom of the container

Water exerts an upwards force on objects. The pressure pushing up on an immersed object is greater than the pressure pushing down on it. The force is known as buoyant force. “Archimedes Principle” explains why objects sink or float. If the buoyant force (upwards force) is equal to the weight of an object, the object will float. If the buoyant force (upwards force) is less than the weight of the object, the object will sink

Example. If you jump in a tub, you will notice that the water exerts an upwards force that keeps you from sinking the bottom right away.

Bernoulli’s Principle reveals that the pressure in a moving stream of fluid is les than that in the surrounding fluid.

Example. A plane’s wings are curved on top and flat on the bottom. Air must travel farther (and faster) over the surface then the bottom, providing a net upwards force beneath the wing.

Due Date: _______________Solids, Liquids and Gases in Depth Summary

1. How would you define matter in your own words?

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_____________________________________________________________________________________________________________________________________________________________________

2. Use your imagination to do one of the following tasks: write a story about what your life would be like if you were

a solid , liquid and gas. Write a riddle about a solid, a liquid and a gas. In your

riddle describe the properties of the material. Ask a friend to guess the material you have described.

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To Recap: The behaviour of matter can be explained using the particle

model. Matter is anything that has mass and takes up space The four states of matter are solid, liquid, gases, and plasma Matter is made up of molecules that are in constant motion Mass is the amount of matter present. It remains constant. The metric basic unit of measure for mass is the gram. Volume is how much space something takes up. The metric unit

of measure for volume is the liter. Density is the relationship between mass and volume. Any material can be described by its qualitative properties, such

as it state and colour, or by quantitative properties, such as melting point and hardness.

Properties determine the ways in which different materials can be used.

Temperature is a quantitative expression of the hotness or coldness of a material

All materials have a characteristic temperature at which they melt or boil.

All matter has a mass and volume Mass is the amount of matter in a material. Mass is measured

using a balance Volume is the amount of space that is occupied by a material. Different methods are used to measure and calculate the

volumes of solids, liquids and gases

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Density is a mathematical calculation of the mass of a material divided by it volume.

Different sample of the same material may have different masses. Their density does not change, however.

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model of molecule web viewthe motion of the particles and the strength of _____ between the...

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