Chapter 2: Chemistry

Question 1

Matter

Answer 1

A physical substance that takes up space and has mass

Question 2

Element

Answer 2

A pure form of matter containing only one kind of atom
Earth is made up of- 100 elements, plus some others
( periodic table)

Question 3

Atom

Answer 3

Is the smallest particle of an element
cannot be broken down by ordinary chemical processes
nucleus contains the mass

Question 4

Subatomic Particles

Answer 4

Protons, Neutrons, and Electrons

Question 5

Protons

Answer 5

• make up the nucleus
• use to determine identity
• has mass
• does not change

Question 6

Neutrons

Answer 6

• no charge
• has mass
• number can change

Question 7

Electrons

Answer 7

• mass is (negligible): to small to change anything

- number can change

Question 8

Elemental composition of organisms

Answer 8

Atom(hydrogen)
Molecule(water)
cell(neuron)
organ(brain)
organism

Question 9

CHNOPS

Answer 9

carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur

make 98% of most living things

Question 10

number of elements important to life

Answer 10

25

Question 11

atomic number

Answer 11

number of protons

Question 12

atomic mass

Answer 12

number of protons and neutrons

Question 13

isotopes

Answer 13

atoms of a particular element all have same number of protons but they can differ in the number of neutrons
EX: Carbon 
carbon -12 (stable)
carbon -13 (stable)
carbon -14 (unstable) radioactive

Question 14

Electrons /

Answer 14

orbits around the nucleus - Shells

inner shells may hold up to 2 electrons and outer shells may hod up to 8 each

Question 15

Valence electrons

Answer 15

electrons in the outermost shell

Question 16

Chemical Bonds

Answer 16

Bonds between atoms are form of chemical energy

Atoms form bonds because doing so moves them to a more stable state

Question 17

Types of bond

Answer 17

covalent
ionic
hydrogen bonds

Question 18

Covalent bonds

Answer 18

Sharing of electrons between atoms

Strongest

Question 19

Ionic Bonds

Answer 19

Transfer of electron between atoms

Ion= charged atom
Oppositely charged ions attract

Strong

Question 20

Hydrogen bonds*

Answer 20

bonds between already covalently bonded hydrogen and an electronegative atom

Question 21

Polarity*

Answer 21

Polar molecules= different areas of the molecule have slightly different charges

Question 22

Hydrophilic

Answer 22

water-loving

Question 23

Hydrophobic

Answer 23

water-hating

Question 24

Water

Answer 24

vertebrate animals 70% - 80% water

terrestrial plants 90%

Question 25

Molecule

Answer 25

A group of atoms bonded together- the smallest fundamental unit of chemical compounds