Cht 2: Chem

Question 1

Matter

Answer 1

Anything that has mass and takes up space

Ex. Solids. Liquids. Gas.

Question 2

Element

Answer 2

Cannot be broken down further by a chem reaction

Ex. Na. Cl.

Question 3

Compound

Answer 3

2+elements combined

Ex. NaCl

Question 4

5 elements that make up 97% human body

Answer 4

Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorus 
(CHiNOP)

Question 5

Atoms

Answer 5

Smallest unit of matter.

Has a central nucleus surrounded by electron shells

Question 6

Proton

Answer 6

+ Positive
In the nucleus
Atomic number

Question 7

Neutron

Answer 7

Neutral (n)

In the nucleus

Question 8

Electrons

Answer 8

Negative
In shells
Octet rule
Atomic number

Question 9

Atomic number

Answer 9

Top number

Tells number of protons and electrons

Question 10

Atomic mass

Answer 10

Bottom number.
Sum of protons and neutrons in the nucleus.
Protons - neutrons =mass

Question 11

Octet rule

Answer 11

Te inner most shell hold up to 2 electrons. The remaining shells hold 8

Question 12

Atom is stable when…

Answer 12

The outter shell is full

Question 13

The chemical behavior (reactive?) depends on…

Answer 13

The valence shell (# e- on the outter shell)

Question 14

Electrically neutral

Answer 14

Number of + protons = - electrons

Question 15

Isotopes

Answer 15

Atoms of the same element (same number of protons) but with varying numbers of neutrons.

Question 16

Relative abundance

Answer 16

When isotopes are average to provide the atomic mss shown on the periodic table

Question 17

Radioactive isotopes

Answer 17

Are unstable and give off radiation as they break down.

Find the age of fossils

Question 18

Ions

Answer 18

Atoms that have gained or lost one or more electrons. Then are no longer electrically neutral.
+ions give
-ions steal
Atoms stable when 8e

Question 19

Chemical bonds

Answer 19

Ionic
Covalent: polar and non
Hydrogen

Question 20

Ionic bonds

Answer 20

Attraction between oppositely charged ions

Ex. Na+Cl-

Question 21

Covalent bonds

Answer 21

When atoms share one or more electrons in order to fill outer shells.
Single and double covalent bonds.
Ex. H2 and O2

Question 22

Polar molecules

Answer 22

Shared electrons spend more time around the more stronger positive nucleus. (-)(+) or (+)(-)
Ex h2o

Question 23

Nonpolar molecules

Answer 23

Shared electrons evenly
(-)(-)or (+)(+)
Ex h2

Question 24

Hydrogen bonds

Answer 24

Weak attractions between the opposite poles of 2 different polar molecules.
Water: surface tension