C1 + C2

Question 1

What is an atom?

Answer 1

The smallest particle of an element that can exist

Question 2

Why do some elements form ions?

Answer 2

Elements form ions to

get a full outer shell, which is more stable

Question 3

What charge would a sodium ion have?

Answer 3

+1

Sodium is in Group 1.

It has one electron in its outer shell.

Question 4

What is an isotope?

Answer 4

An isotope is

an atom that has more neutrons than usual (but the same number of protons).

Question 5

What is an element?

Answer 5

A substance that contains only one sort of atom

Question 6

What is a compound?

List the elements in these compounds:

1. CaSO4
2. Magnesium nitrate Mg(NO3)2

Answer 6

A substance that is made of two or more different types of atoms that are chemically bonded together.

1. calcium,sulfur, oxygen
2. magnesium, nitrogen, oxygen

Question 7

What is a solvent?

Answer 7

The liquid that does the dissolving.

e. g. the water in sea water

Question 8

What is a solution?

Answer 8

Liquid with solid disolved in.

e. g. sea water (liquid and solid together)

Question 9

What is a solute?

Answer 9

Solid that gets dissolved.

e. g. the salt in the sea water

Question 10

What is soluble?

Answer 10

can dissolve in liquid

e. g. salt is soluble in water

Question 11

What is insoluble?

Answer 11

Can not dissolve.

e. g. sand is insoluble in water

Question 12

Filtration

What is this separation technique used for?

Answer 12

Filtration separates insoluble solids from mixtures.

e.g. sand can be separated from salt using filtration

Question 13

What is this separation technique used for?

Distillation

Answer 13

Distillation is separating mixtures of liquids with different boiling points.

e.g. pure water can be distilled from sea water

Question 14

Evaporation

What is this separation technique used for?

Answer 14

Evaporation is used to remove solvents from solutions.

e.g. a salt can be separated from a solution by heating it until the solvent (liquid) evaporates.

Question 15

Chromatography

What is this separation technique used for?

Answer 15

Chromatography is used for separating dyes from mixtures.

e.g. different dyes in food colourings

Question 16

What was the plum-pudding model of an atom?

Answer 16

A ‘blob’ of positive charge with negative charged electrons arranged at random throughout.

Question 17

What did Rutherford discover and how did he observe it?

Answer 17

He discovered the nucleus by firing alpha particles at a thin gold sheet of foil and observing their interaction. He saw roughly 1/7000 particles were reflected back, indicating a solid nucleus at the core.

Question 18

Explain how Mendeleev arranged the elements in the Periodic Table. Why did he leave gaps?

Answer 18

He organised the Periodic Table

in order of increasing atomic mass.

He left gaps for undiscovered elements.

Question 19

Complete the following word equations:

1. Potassium chloride + fluorine
2. Sodium fluoride + iodine
3. Magnesium iodide + bromine

Answer 19

1. Potassium fluoride + chlorine

2. NO REACTION

3. Magnesium bromide + iodine

Question 20

Which are the properties that you would expect magnesium to have?

Sonorous, low boiling point, hard,

dull, brittle, insulator, ductile, conductor

high melting point

Answer 20

Sonorous

ductile

conductor

high melting point

Question 21

Balance the following equations:

H2 + Cl2 → HCL

Zn + O2 → ZnO

Cl2 + Al → AlCl3

Fe2O3 + Al → Fe + Al2O3

Answer 21

H2 + Cl2 → 2 HCL

2 Zn + O2 → 2 ZNO

3 Cl2 + 2 Al → 2 AlCl3

Fe2O3 + 2 Al → 2 Fe + Al2O3

Question 22

What is the mass and the charge?

Answer 22

Question 23

What are the number of protons, electrons, neurons and Electronic structure?

Answer 23

Question 24

Complete the equations:

Answer 24

Question 25

Label the diagram, describe the structure, name the element shown

Answer 25

Question 26

What are mixtures?

Answer 26

Two or more elements or compounds which are **NOT CHEMICALLY COMBINED**

Question 27

How can mixtures be separated?

Answer 27

mixtures can be separated by: 1. filtration 2. evaporation (crystallisation) 3. distillation 4. chromatography

Question 28

How is an element different to a compound?

Answer 28

**Elements** contain just **one type of atom**, **compounds** contain atoms of **at least two different elements** which have been chemically combined

Question 29

What does the formula CaCO₃ tell you about the compound calcium carbonate?

Answer 29

It contains: 1 Calcium atom 1 carbon atom 3 Oxygen atoms

Question 30

What process can be used to extract pure water from salt water?

Answer 30

Simple distillation

Question 31

What do atoms contain?

Answer 31

Subatomic particles called: Protons Neurons Electrons

Question 32

What is the charge or Protons? What is the relative mass of protons?

Answer 32

Protons Charge: +1 Relative mass: 1

Question 33

What is the charge of Neutrons? What is the relative mass of Neutrons?

Answer 33

Neutrons Charge: no charge Relative mass: 1

Question 34

What is the charge of electrons?

Answer 34

Electrons Charge: -1 Relative mass: very small

Question 35

What is the top number on a symbol?

Answer 35

The Mass number (number of protons + neutrons)

Question 36

What is the bottom number on a symbol?

Answer 36

The atomic number (number of electrons)

Question 37

How do you calculate the number of neutrons?

Answer 37

Top number - Bottom number = number of neutrons

Question 38

What is the electronic structure of an atom?

Answer 38

Shows how the electrons are arranged around the nucleus in shells (energy levels). first shell = max 2 electrons next two shells= max 8 electrons

Question 39

An atom of potassiu has an atomic number of 19 and a mass number of 39. State the number of protons, electrons and neutrons of this atom.

Answer 39

19 Protons 19 Electrons 20 Neutrons

Question 40

An ion of potassium -39 has a +1 charge. State the number of protons, neutrons and electrons in the ion.

Answer 40

19 protons 18 electrons 20 neutrons

Question 41

How are the elements in the periodic table organised?

Answer 41

Elements that have the same number of electrons in their outer shell have similar properties. They are in the same group. e.g. Group 1 elements all have one electron in their outer shell

Question 42

What group are noble gases in? Why are the very unreactive?

Answer 42

Group 0 They are unreactive because their outer shell of electrons is full so they don't need to react with other elements.

Question 43

What are group one elements called? What are their properties?

Answer 43

**Alkali metals** * They have o**ne electron in their outer shell.** * they have **low melting and boiling points** * they are **very reactive** with oxygen and water * they have **low density** * they **react with non-metal**s to form ionic compounds

Question 44

How do group one elements change going **down** the group?

Answer 44

* boiling and melting points **decrease** * they become **more reactive** as the outer electron is lost more easily

Question 45

What do group 1 metals from with oxygen? eg. sodium + oxygen = ?

Answer 45

They form metal oxides. eg. sodium + Oxygen= sodium oxide

Question 46

What happens when lithium, sodium and potassium are put in water? Why?

Answer 46

They float on top of it because they are less dense than water.

Question 47

How do alkali metals react with water? eg, potassium + water = ?

Answer 47

They form a metal hydroxide and hydrogen gas is given off. eg. potassium + water = potassium hydroxide + hydrogen

Question 48

What are the group 7 elements called? What are their properties?

Answer 48

They are **non-metals** known as **halogens.** * they have **7 electrons** in their outer shell * they react with metals to produce **salts** * The **reactivity decreases down the group** as it becomes less easy to gain an electron * A **more reactive halogen will displace a less reactive halogen**

Question 49

What are the diplacement reactions? Chlorine + Potassium bromide = ? chlorine + potassium iodide =? bromine + potassium iodide=?

Answer 49

Chlorine will displace bromine from potassium bromide ## Footnote chlorine + potassium bromide = potassium chloride + bromine chlorine + potassium iodide = potassium chloride + iodine bromine + potassium iodide= potassium bromide + iodine

Question 50

Why are group 0 elements unreactive?

Answer 50

They have a full outer shell which is a stable arrangement.

Question 51

Why are alkali metals stored in oil?

Answer 51

Because they are highly reactive they are stored in oil to To stop them from reacting with oxygen or water (moisture) in the air