Units of Measurement

Drill # 8 9/4/2014

Write drill # 8 and the date in your notebook

Copy the questions (they are on the right side of the board)

Answer 7 minutes, everyone is quiet

and in her/his seat

Topic: Units of Measurement

Objective: Students will be able to Name the basic metric

units and give examples of derived units

Measure length and liquid volume

HW #7: Get worksheet

Number vs. Quantity

Quantity - number + unit

No Naked Numbers! UNITS MATTER!!

SI Units (copy)

Quantity Base Unit Symbol

Length

Mass

Time

Temp

meter

kilogram

second

kelvin

m

kg

s

K

Current ampere A

Changing the size of SI Units

mega- M 106

deci- d 10-1

centi- c 10-2

milli- m 10-3

Prefix Symbol Factor

micro- 10-6

nano- n 10-9

pico- p 10-12

kilo- k 103

Derived Units (copy)

Combination of base units. Derived by multiplying or dividing

quantities to get new quantities Volume = length length length

cm x cm x cm = cm3

1 cm3 = 1 mL 1 dm3 = 1 L Density = mass /volume (g/cm3)

The Metric System

In science class we use the Metric System.

The metric system is simpler and easier to use

Most countries only use the metric system.

In the US we still use the English System except in science.

1 inch = 2.54 centimeters

Compare

1 mile = 1.6 km

1 yard = 0.9444 meters

The ruler

1 cm = 10 mm

What is the length of the line in centimeters? 2.80 cm

What is the length of the line in millimeters?

28.0 mm

Correct way to record measurement

(copy) Include all digits below the

mark Add one more digit that is

estimated If the mark is exactly on the line

you still have to add the extra digit make it “0” This is how you tell that the mark was

on the line

Measuring Volume of Liquids (copy)

Graduated cylinder

The curve is called meniscus

Place cylinder on level surface

Move so your eyes are at meniscus level

Read the “ruler” at the bottom of the meniscus

What causes meniscus(copy)

The molecules of the liquid stick to the walls of the cylinder

Parallax error-when you are looking at an angle

Parallax error

What is the volume?

A. 52.0 mL

B. 37.0 mL

C. 26 mL

Derived unit for Density

You have a sample with a mass of 620 g & a volume of 753 cm3. Find density.

GIVEN:

M = 620 g

V = 753 cm3

D = ?

DM

V

WORK:

D = M V

D = 620 g

753 cm3

D = 0.82 g/cm3

Drill # 9 9/5/2014

Write drill # 9 and the date in your notebook

Copy the questions (they are on the right side of the board)

Answer 7 minutes, everyone is quiet

and in her/his seat

Topic: Measuring Part I

Objective: Students will be able to

Use proper tecniques to measure length and liquid volume

HW Free Friday

Guided Practice

Group work Individual paper! Choose your role Obtain worksheet Obtain materials Read directions Complete

assignment Return materials 20 minutes

Materials Rulers 10 pennies Graduated cylinder Eye dropper Cup Water in the cup

Did we achieve objectives?

Objective: Students will be able to

Name the basic metric units and give examples of derived units

Measure length and volume

What is your HW for tonight

1.Complete the HW#7 worksheet

Exit Ticket ID#, in your seat, and quiet Questions:1. Name the unit for:a)massb)Timec)Temperatured)Length2. What is meniscus (in

chemistry) ?