Chemistry Sesson 1

Question 1

Solution

Answer 1

a mixure of one substance dissolved in another so the properties are the same throughout. It is composed of a solute and the solvent

Question 2

Aqueous solution

Answer 2

If a solid has dissolved into a liquid

Question 3

Soluble

Answer 3

solids that dissolve

Question 4

Insoluble

Answer 4

solids that don’t dissolve

Question 5

Hydrated crystals

Answer 5

if the crystals contain molecules of water

Question 6

Anhydrous

Answer 6

without water

Question 7

Crystallisation

Answer 7

the process of obtaining crystals by evaporating water from a solution

Question 8

Saturated solution

Answer 8

when there’s too much solute that the solvent can’t dissolve it

Question 9

Anti-bumping granules

Answer 9

a tiny, unevenly shaped piece of substance added to liquids to make them boil more calmly. It provides more surface area for the condensation of vapor as to prevent excessive boiling.

Question 10

Distillation

Answer 10

The process of boiling a liquid and then condensing the vapor produced back into a liquid: used to purify liquids and to separate liquids from solutions

Question 11

Solvent

Answer 11

The liquid that dissolves the solid solute to from a solution; water is the most common solvent

Question 12

Solution

Answer 12

formed when a substance (solute) dissolves in another substance (solvent)

Question 13

Solute

Answer 13

the solid substance that has dissolved in a liquid (the solvent) to form a solution

Question 14

Distillate

Answer 14

The liquid distilling over during distillation

Question 15

Function of glass beads in fractional distillation

Answer 15

they provide a cooling surface for condensation back into a liquid

Question 16

Fractional distillation

Answer 16

separates 2 solvents that can mix with each other. The 2 solvents have different boiling points.

Question 17

Chromatography

Answer 17

the separation of differnt pigments which have different solubility’s in a solvent (e.g water)

Question 18

Difference between pure and impure substances

Answer 18

Pure- sharp melting point, all liquid boils at the same temparature, usually only produces one spot on the chromatogram. Impure- melts over a temparature range and at a lower temperature than a pure solid. Bouls over a temparature range- starts to boil at the boiling point of one liquid and rises to the boiling point of the other. Produces more than one spot

Question 19

Chemical change

Answer 19

usually a permanent color change, a temperature change or a gas given off. New chemicals are made and the reaction is not easily reversed.

Question 20

Physical change

Answer 20

no new substances made, usually a change of state, reversible.

Question 21

Element + element reactions

Answer 21

the non-metal changes to end in -ide

Question 22

Metal+ acid

Answer 22

salt + hydrogen

Question 23

Metal carbonate+ acid

Answer 23

salt+ water + carbon dioxide

Question 24

Acid+ alkali

Answer 24

salt+ water

Question 25

Metal+ salt solution

Answer 25

displacement

Question 26

atom

Answer 26

the smallest part of an element that can exist. It can't be broken down into anything further

Question 27

Molecule

Answer 27

two or more atoms of the same or different elements chemically bonded together

Question 28

Elements

Answer 28

a single substance with only one type of atom

Question 29

Compounds

Answer 29

when two or more different elements are chemically combined together (ionic or covalent bonds are formed). They are fixed in their compositions by mass or elemnts present. Chemicals react to form new substances. It cannot be separated by physical methods.

Question 30

Mixtures

Answer 30

Can be separated from one another using physical methods (e.g distillation, magnetic attraction, etc). Mixing not usually accompanied by external effects, no reaction takes place. Properties of the substances present remain the same

Question 31

Isotope

Answer 31

Different atoms of the same element, with the same number of protons and electrons but different number of neutrons

Question 32

Base

Answer 32

a substance that neutralizes an acid

Question 33

Alkali

Answer 33

a soluble base

Question 34

Alkali metals

Answer 34

a metal in group 1 of the Peridodic table. They react to form ionic compounds with non-metals

Question 35

Alkali earth metal

Answer 35

A metal in group 2 of the Periodic table.

Question 36

Halogen

Answer 36

An element in group 7 of the Periodic table. The word halogen means "salt producer". They are diatomic. They form molecular compounds with other non-metallic elements. A more reactive halogen can displace a less reactive halogen.

Question 37

Why is group 1 known as the alkali metals?

Answer 37

Because they produce a hydroxide

Question 38

Storage method of alkali metals

Answer 38

in parafin oil

Question 39

Reactivity down the group of alkali metals, why?

Answer 39

become increasingly more reactive, because there are more outermost shells, and therefore it is easier for the element to lose its electron

Question 40

Reactivity down the group of halogens, why?

Answer 40

decreases down the group, as there are more outermost shells, and therefore it is harder for the element to gain an electron

Question 41

Colors down the group of halogens

Answer 41

gets darker

Question 42

Features of transition metals

Answer 42

high densities, high melting points, form colored compounds which act as catalysts

Question 43

Why are noble gases inert?

Answer 43

they do not need to taken in or give out any electrons

Question 44

Uses of argon

Answer 44

light bulbs, as it doesn't react with the metal filament

Question 45

Uses of helium

Answer 45

used with oxygen for deep sea dives, as there's a low solubility of helium in the blood. To inflate the tyres of large aircrafts, as it is non-flammable. To fill airships and weather ballopns, as they have a low density and are non-flammable

Question 46

Neon

Answer 46

used in advertising signs (it glow red when electricity passes), as it is a conductor of electricity at high voltage

Question 47

Krypton/Xenon

Answer 47

In lamps used in photographic flash uits, as it gives out a lot of light when electrivity passes through