Chemistry - Chemistry Definitions

Question 0

Homogeneous mixtures

Answer 0

Same consistency all the way through

Question 1

Mixtures

Answer 1

Substances that are physically combined. Are impure

Question 2

Heterogeneous mixtures

Answer 2

Different consistency all the ways through

E.g. Marbles and sand

Question 3

Pure substances

Answer 3

A single substance containing no other substances

Question 4

Elements

Answer 4

Simplest pure substance that can’t be broken down. About 90 occur naturally

Question 5

Compounds

Answer 5

Two or more elements chemically combined

Question 6

Atoms

Answer 6

Make up all substancesi. Small particles

Question 7

Metalloids/Semi-metals

Answer 7

Not metals or non-metals. Resistance decreases as the temperature increases.

Question 8

Kinetic Molecular Theory

Answer 8

Explains the motion behavior of solids, liquids and gases

Question 9

Brownian Motion

Answer 9

Random motion of particles

Question 10

Temperature

Answer 10

Degree of hotness/coldness. Measure of internal energy of particles measured in Celsius.

Question 11

Heat

Answer 11

Transit of energy due to temperature difference

Question 12

Electron configuration

Answer 12

Arrangement of electrons

Question 13

Quantized

Answer 13

Electron contains a certain amount of energy

Question 14

Valence electrons

Answer 14

Outer electrons on the last energy level

Question 15

Core electrons

Answer 15

Rest of electrons in atoms

Question 16

Intermolecular forces

Answer 16

Hold solids and liquids together

Question 17

Octet rule

Answer 17

Electrons generally try get an outer ring of eight electrons

Question 18

Chemical bonding

Answer 18

Interactions between matter creating substances with new physical/chemical properties.

Question 19

Electronegativity

Answer 19

A number rating how strongly the atom pulls the bonded electrons to itself

Question 20

Ion

Answer 20

Small charged particle which has lost/gained electrons

Question 21

Valency

Answer 21

Number of valence electrons

Question 22

Anions

Answer 22

Negatively charged ions

Question 23

Cations

Answer 23

Positively charged electrons

Question 24

Stock notation

Answer 24

Roman numerals used to show valency of transition metals (e.g. iron II)

Question 25

Electron affinity

Answer 25

Amount of energy released per mole when an atom gains an electron

Question 26

Atomic Mass Unit (1 a.m.u.)

Answer 26

One twelfth of the mass of a carbon-12 atom.

1 a.m.u. = 1.66 x 10^-27 kg

Question 27

Elemental unit of charge (e)

Answer 27

Smallest unit of electronic change
Electron : -1.6 x 10^-19 C
Proton : 1.6 x 10^-19 C