unit 1 chemistry of life: atoms and molecules. elements required for life approx 25 elements c, o, h...
TRANSCRIPT
![Page 1: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/1.jpg)
Unit 1 Chemistry of Life: Atoms and Molecules
![Page 2: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/2.jpg)
Elements Required for LifeApprox 25 elementsC, O, H and N 96% of living matterP, S, Ca and K 4% of an organism’s weightTrace elements
Needed in minute quantities Ex. Fe, I, Mg
![Page 3: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/3.jpg)
MatterAnything that takes up space and has massSolid, liquid, gasElements cannot be broken down further
Fe, Rb, FrCompounds consist of two or more elements
NaCl, H2O, H2CO3
![Page 4: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/4.jpg)
Periodic Table of Elements
GroupsPeriodsAtomic
numberAtomic
massMetals/
NonmetalsFamiliesTrends
![Page 5: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/5.jpg)
Chemical FamiliesAlkali metalsAlkaline earth metalsMetalloidsHalogensNoble gasesTransition metalsActinide/Lanthanide Series
![Page 6: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/6.jpg)
Atomic Structure
Atom-Smallest unit of matter Subatomic particles-Parts of atom
Neutron/proton
mass=1.7X10-24 g (1
Da or amu)
Mass of electron is negligible (1/2000)
![Page 7: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/7.jpg)
Atomic Number and Weight
All atoms of an element have same number of protons; this is atomic number
2HeAll atoms have a balanced charge, therefore:
Atomic number=Protons=ElectronsMass number=Protons + neutrons (round
mass #)Mass number – atomic number
(protons)=NeutronsAll of atom’s mass is in nucleus; this is atomic
weight
![Page 8: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/8.jpg)
Isotopes
Atoms of a given element that contain different number of neutrons, but same protons
All natural elements exist as a mixture of all its isotopes
Some are radioactive isotopes which have a spontaneously decaying nucleus Radiology
![Page 9: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/9.jpg)
Energy Levels
Each electron shell contains a certain amount of energy (n)
As you move up the energy increases
e- moving up absorbs energye- moving down loses energy,
releasing heat# e- in each level=2(n)2
For atomic structure: Place neutrons and protons in
nucleus Arrange e- using 2n2
![Page 10: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/10.jpg)
Valency
The number of electrons that orbit the outermost energy level
This is equivalent to the charge
![Page 11: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/11.jpg)
Chemical Bonding
All bonding occurs in the outer shell of atoms (sharing of valance e-)
Types of bonds: Covalent Bonds-Sharing of a pair of valence electrons by two
atoms. Non polar covalent: e- are shared equally (methane) Polar covalent: Unequal sharing of e-. One tends to pull harder
(HCl or water) Ionic Bonds-Transfer of e- from the negative ion to the positive
ion. Ion-Element that loses or gains an electron
Hydrogen Bonds-Hydrogen atoms bonded to electronegative atoms
Van Der Waals Interactions-All atoms and molecules when close to each other tend to “stick” to one another. Occurs due to natural gravitational forces of atoms
![Page 12: Unit 1 Chemistry of Life: Atoms and Molecules. Elements Required for Life Approx 25 elements C, O, H and N 96% of living matter P, S, Ca and K 4%](https://reader036.vdocuments.net/reader036/viewer/2022062516/56649d825503460f94a67894/html5/thumbnails/12.jpg)
Non-Polar