Chemistry Ka2

Question 1

What is oxidation?

Answer 1

When oxygen is added to an element

Question 2

What is reduction?

Answer 2

When oxygen is lost or removed from a compound

Question 3

What has happened here? :

4Na + O₂ –> Na₂O

Answer 3

Oxidation of sodium

Question 4

In terms of electrons, what is oxidation?

Answer 4

The loss of electrons

Question 5

What is the sentence for the reactivity series?

Answer 5

Please Send Lions, Cats, Monkeys and Zebras Into Lovely Hot Countries, Signed General Penguin

Question 6

What happens the the most reactive group in the reactivity series?

Answer 6

They burn to form oxide

Question 7

What happens to the middle group in the reactivity series?

Answer 7

Forms oxide when heated

Question 8

What happens to the least reactive metals in the reactivity series?

Answer 8

No reaction

Question 9

What is the word equation for reaction with cold water?

Answer 9

Metal + water –> metal hydroxide + hydrogen

Question 10

What metals will react with cold water?

Answer 10

Metals with high reactivity

Question 11

What metals react with dilute acids?

Answer 11

Metals that are more reactive than hydrogen

Question 12

What is the word equation for reaction with dilute acids

Answer 12

Metal + acid –> salt + hydrogen

MASH

Question 13

Explain what happens with Li - 2e

Answer 13

The element becomes positively charged because you have taken away some of the negative charge

Question 14

Explain oxidation and reduction with: CuO + H₂ –> Cu + H₂O

Answer 14

Oxidation of hydrogen

Reduction of copper oxide

Question 15

What happens when metal atoms react?

Answer 15

They lose electrons to form positive ions

Question 16

Write an equation to show what happens to the magnesium atoms when they react and form magnesium ions (Mg2+)

Answer 16

Mg - 2e⁻ –> Mg²⁺

Question 17

What is the rule thingy for metals more reactive than hydrogen?

Answer 17

If a metal is more reactive than hydrogen, the metal will react with an acid. If a metal is less reactive than hydrogen, the metal will not react with an acid

Question 18

What do all acids contain?

Answer 18

A hydrogen ion

Question 19

What does OILRIG mean?

Answer 19

Oxygen is loss of electrons

Reduction is gain

Question 20

Is this oxidation or reduction?

2Br⁻ - 2e⁻ –> Br₂

Answer 20

Oxidation

Question 21

Is this oxidation or reduction?

Cu²⁺ + 2e⁻ –> Cu

Answer 21

Reduction

Question 22

Is this oxidation or reduction?

Al³⁺ + 3e⁻ –> Al

Answer 22

Reduction

Question 23

Is this oxidation or reduction?

2Cl⁻ - 2e⁻ –> Cl₂

Answer 23

Oxidation

Question 24

What happens when a positive ion changes into an Atom?

Answer 24

The positive ion always gains electrons. The positive ion is always reduced

Question 25

What happens when a negative ion changes into an atom?

Answer 25

The negative ion always loses electrons. The negative ion is always oxidised

Question 26

Balance this equation by putting a number where indicated (___) ___F⁻ - 2e⁻ --> F₂

Answer 26

2F⁻ - 2e⁻ --> F₂

Question 27

Balance this equation by putting a number where indicated (___) Al³⁺ + __e⁻ --> Al

Answer 27

Al³⁺ + 3e⁻ --> Al

Question 28

Balance this equation by putting a number where indicated (___) ___O² - 4e⁻ --> O₂

Answer 28

2O² - 4e⁻ --> O₂

Question 29

What does extract mean?

Answer 29

To take something out of something

Question 30

What do potassium, sodium and lithium need to pass through their ores?

Answer 30

Electricity

Question 31

What is an ore?

Answer 31

A rock which has a compound from which a metal can be extracted

Question 32

What is reduced and what is oxidised? Zinc oxide + carbon --> zinc + carbon dioxide

Answer 32

Zinc oxide - reduced | Carbon - oxidised

Question 33

What is oxidised and what is reduced? Copper oxide + carbon --> carbon dioxide + copper

Answer 33

Copper oxide - reduced | Carbon - oxidised

Question 34

When metals are extracted from compounds, what happens to the metal ions in the compounds?

Answer 34

They gain electrons

Question 35

Copper reacts with silver nitrate solution, complete the word equation : Copper+silver nitrate --> _______ + ________

Answer 35

Copper + silver nitrate --> copper nitrate + silver

Question 36

Magnesium + copper sulphate --> magnesium sulphate + copper Why is this called a displacement reaction?

Answer 36

Because magnesium is more reactive than the copper and takes the place of copper to make magnesium sulphate

Question 37

What is a dependant variable?

Answer 37

Something that will/can change

Question 38

What are the variables?

Answer 38

Something that will/can/should stay the same

Question 39

What is lithium, potassium and sodium kept in and why?

Answer 39

Paraffin oil to stop them from reacting with any water or oxygen in the air

Question 40

Lithium, potassium and sodium are what when they are first cut?

Answer 40

Shiny

Question 41

Potassium, lithium and sodium do what on water and what does this mean?

Answer 41

They float meaning they are less dense

Question 42

What happens to lithium, potassium and sodium when they react?

Answer 42

They get smaller and bubbles of gas can be seen and when the reaction has ended there is no (metal) left

Question 43

Do lithium, potassium and sodium all react with water?

Answer 43

Yes

Question 44

If a solution turns universal indicator purple, what does it mean?

Answer 44

The solution is an alkali

Question 45

What if metal two is more reactive than metal 1?

Answer 45

The voltage measured is positive

Question 46

What is metal one is more reactive than metal two

Answer 46

The voltage measured is negative

Question 47

The bigger the difference in reactivity of the two metals, _______________________________

Answer 47

The larger the voltage produced

Question 48

Zn - 2e⁻ --> Zn²⁺ Zinc is oxidised in this reaction, why?

Answer 48

Because zinc has lost electrons