1 - Fundamental Chemistry

Question 1

Solid to liquid?

Answer 1

melting

Question 2

Liquid to gas?

Answer 2

Evaporating

Question 3

Solid to gas?

Answer 3

sublimation

Question 4

Gas to solid?

Answer 4

deposition

Question 5

Gas to liquid?

Answer 5

condensing

Question 6

Liquid to solid?

Answer 6

freezing

Question 7

Describe the particles in a solid

Answer 7

• particles are held tightly packed and fairly close together
• particles are in fixed positions but they do vibrate
• particles are strongly attracted to each other

Question 8

Describe the particles in a liquid

Answer 8

• particles are fairly close together with some attraction between them
• particles are able to move around in all directions but movement is limited by attractions between particles

Question 9

Describe the particles in a gas

Answer 9

• particles are free to move in all directions and collide with each other and with the walls of the container and are widely spaced out
• particles have little attraction between them

Question 10

What happens as the water changes states?

Answer 10

• bonds are being broken and particles are rearranging all of which requires energy

Question 11

Define diffusion

Answer 11

• movement of particles from an area of high concentration to an area of low concentration

Question 12

Why does diffusion occure faster in a hot solution?

Answer 12

• the particles have more kinetic energy so move around faster

Question 13

Define solute

Answer 13

Substance (often a solid) to be dissolved

Question 14

Define solvent

Answer 14

Liquid that can dissolve a solid

Question 15

Define solution

Answer 15

A mixture formed when one substance dissolves into another

Question 16

Define soluble

Answer 16

Can dissolve

Question 17

Define insoluble

Answer 17

Cannot dissolve

Question 18

Define saturated

Answer 18

As much solute is dissolved into the solvent as is possible

Question 19

Define aqueous

Answer 19

The substance is dissolved in a solution

Question 20

What is the formula for hydrochloric acid?

Answer 20

HCl

Question 21

Which state of matter has the highest energy?

Answer 21

Gas

Question 22

What is H2SO4?

Answer 22

Sulfuric acid

Question 23

What is the unit for solubility?

Answer 23

g/100g

Question 24

What is the relationship between solubility and temperature?

Answer 24

The lower the solubility of the substance, the lower the temperature of cristalisation

Question 25

Define element

Answer 25

A substance made of only one type of atom

Question 26

Define compound

Answer 26

Two or more types of atoms that are chemically bonded

Question 27

Define mixture

Answer 27

Two substances together that are not chemically bonded

Question 28

Define molecule

Answer 28

Two or more atoms bonded together

Question 29

Define atom

Answer 29

The smallest part of an element

Question 30

What are the 4 ways of seperating mixtures?

Answer 30

- chromatography - filtration - evaporation - distillation (simple or fractional) 

Question 31

What is filtration?

Answer 31

To seperate an insoluble solid from a liquid eg. sand + water

Question 32

What is simple distillation?

Answer 32

- to seperate a solute and a solvent when we want to keep both - the temperature needs to be above the boiling point of the solvent

Question 33

What is fractional distillation?

Answer 33

- to seperate mixtures of liquids with different boiling points 

Question 34

Apparatus for simple distillation:

Answer 34

- bunsen burner - boiling tube - bung - thermometer - delivery tube - beaker

Question 35

Apparatus for fractional distillation:

Answer 35

- round-bottomed flask - fractional distillation column - bung - thermometer - Liebig condenser - conical flask

Question 36

What do long molecules have that makes them hard to break?

Answer 36

They have a higher boiling point

Question 37

What is chromatography?

Answer 37

As the solvent rises up the filter paper, the individual components (dyes) within the substance are seperated. Different dyes travel different distances up the paper.

Question 38

What is the solvent front?

Answer 38

The solvent that travels the furthest up the filter paper which leaves a line. 

Question 39

How to calculate an Rf value

Answer 39

distance travelled by substance/distance travelled by solvent

Question 40

What are the 3 subatomic particles?

Answer 40

- protons - neutrons - electrons

Question 41

What is the nucleus of an element made of?

Answer 41

- neutrons (neutral charge) | - protons (+ charge)

Question 42

What is the mass number?

Answer 42

- number of protons and neutrons  | - number below the symbol of the element

Question 43

What is the atomic number?

Answer 43

- number of protons and electrons | - below the symbol of the element

Question 44

How to calculate the number of neutrons?

Answer 44

atomic mass (protons+neutrons) - atomic number (protons)

Question 45

How do you calculate the number of electrons?

Answer 45

The atomic number (below the symbol) 

Question 46

What is the mass of a proton?

Answer 46

1

Question 47

What is the mass of a neutron?

Answer 47

1

Question 48

What is the mass of an electron?

Answer 48

negligable

Question 49

What is an isotope?

Answer 49

When the number of neutrons change. This changes the mass number. 

Question 50

What are shells?

Answer 50

The electrons surrounding the nucleus in energy levels.

Question 51

What are isotopes?

Answer 51

Isotopes are atoms that have the same number of protons but different numbers of neutrons in their nuclei. 

Question 52

How to calculate the atomic mass of an isotope?

Answer 52

(percentage by atomic mass) + (percentage by atomic mass)/100

Question 53

Define relative atomic mass

Answer 53

Mass of an atom relative to the mass of Carbon-12