Gr.11 T4 Chemistry

Question 1

What is an acid according to the Arrhenius model?

Won’t need to spell

Answer 1

Ionises in water to produce the hydrogen ion

Question 2

What is a base according to the Arrhenius model?

Answer 2

Ionises in water to produce the hydroxide ion

Question 3

What is an acid according to the Bronsted-Lowry model?

Answer 3

A proton donor

Question 4

What is an a base according to the Bronsted-Lowry model?

Answer 4

A proton acceptor

Question 5

Ampholytes

Answer 5

A substance that can act as an acid or base

Question 6

Learn common acids and bases on p.242

Answer 6

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Question 7

What are the 4 types of reactions of acids and bases?

Answer 7

Acid+metal ➡️ salt+hydrogen (electron transfer - redox rection)

Acid+metal hydroxide ➡️ salt+water (neutralisation)

Acid+metal oxide ➡️ salt+water

Acid+metal carbonate ➡️ salt+water+carbon dioxide

Question 8

What are the properties of acids and bases?

Answer 8

Acids:
Taste sour.
Their aqueous solutions conduct electricity (called electrolytes)
React with certain metals to produce hydrogen gas
CO2 produced when acids react with limestone

Bases:
Taste bitter
Solutions of alkalis, bases that are soluble in water, conduct electricity (called electrolytes)
Generally feel slippery/ soapy

Question 9

What is the colour of red litmus in an acid, base and neutral substance?

Answer 9

Acid: red

Base: blue

Neutral: red

Question 10

What is the colour of blue litmus in an acid, base and neutral substance?

Answer 10

Acid: red

Base: blue

Neutral: blue

Question 11

What is the colour of phenolphthalein in an acid, base and neutral substance?

Answer 11

Acid: colourless

Base: pink

Neutral: colourless

Question 12

What is the colour of bromothymol blue in an acid, base and neutral substance?

Answer 12

Acid: yellow

Base: blue

Neutral: light green

Question 13

What is the colour of methyl orange in an acid, base and neutral substance?

Answer 13

Acid: red

Base: orange

Neutral: orange

Question 14

Indicators

Answer 14

Organic substances that change colour in acids and bases.

Question 15

What is universal indicator?

Answer 15

A mixture of dyes that can change into many different colours. (Shows the full range of pH colours)

Question 16

Titation

Answer 16

A process used to neutralise an acid or base and to determine the concentration of an unknown solution.

Question 17

Oxidation

Answer 17

A loss in electrons

Question 18

Reduction

Answer 18

A gain in electrons

Question 19

Oxidation number/ oxidation state

Answer 19

A number assigned to each atom to keep track of electrons during a reaction

Question 20

Give one exception to oxygen having an oxidation state of -2 (the only one I need to know)

Answer 20

H O
2 2

Oxygen has an oxidation state of -1

Question 21

What is a reducing agent?

Answer 21

A substance that causes reduction but it itself is oxidised

Question 22

What is an oxidising agent?

Answer 22

A substance that causes oxidation but it itself is reduced

Question 23

What is a redox reaction?

Answer 23

The transfer of electrons

Question 24

When does a hydrogen ion have an oxidation state of +1 and when does it have an oxidation state of -1?

Answer 24

+1 when bonded to non-metals

-1 when bonded to metals

Question 25

What are the 3 classifications of redox reactions?

Answer 25

1. Displacement reaction 2. Synthesis reaction (2+ reactants, 1 product) 3. Decomposition reaction (1 reactant, 2+ products)

Question 26

What are the tests for oxygen gas and hydrogen gas?

Answer 26

Oxygen gas: glowing splint relights Hydrogen gas: burning split ignites gas with popping sound

Question 27

Electrochemical reaction

Answer 27

Oxidation and reduction take place in separate compartments

Question 28

What energy transformation happens in an electrochemical reaction?

Answer 28

Chemical energy becomes electrical energy

Question 29

Electrochemical cell

Answer 29

Energy from the redox reaction is used as a source of electric current

Question 30

What happens at the anode and the cathode (oxidation/ reduction)? Does this cause the electrode to increase or decrease in mass?

Answer 30

Anode: oxidation (electrode decreases in mass) Cathode: reduction (electrode increases in mass)

Question 31

What are the two functions of the salt bridge in an electrochemical cell?

Answer 31

It completes the circuit and it ensures that the electrolytes remain neutral

Question 32

Give the formula for the dichromate ion

Answer 32

-2 Cr O 2 7

Question 33

In electrochemical cells, electrons flow through the wire and ions flow through the salt bridge and electrolytes

Answer 33

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Question 34

What is an electrochemical cell called if it has: 1) a spontaneous chemical reaction between chemicals 2) a non-spontaneous chemical reaction driven by chemical energy

Answer 34

1) galvanic cell (or voltaic cell) | 2) electrolytic cell

Question 35

What is the name of the process that occurs in an electrolytic cell?

Answer 35

Electrolysis

Question 36

Cell potential

Answer 36

The potential difference between the cathode and anode

Question 37

What is a standard electrode potential?

Answer 37

The voltage measured under standard conditions when the half-cell is connected to a standard hydrogen electrode to form an electrochemical cell. (Measured in V)

Question 38

What are standard conditions?

Answer 38

p = 1 atm -3 c = 1 mol.dm temp.= 25*C

Question 39

Why is a platinum electrode used in a hydrogen half-cell?

Answer 39

It is chemically inert and a good electrical conductor.

Question 40

Look at how to write equations using table 4A

Answer 40

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