Chemical Changes for Separate Science

When a metal reacts with oxygen what is produced?

Metal oxides

What type of reaction is the reaction between a metal and oxygen?

Oxidation

When metals react with other substances the metal atoms form?

Positive ions

When metals react with other substances the metal atoms form?

Positive ions

When metals react with other substances the metal atoms form?

Displace it

What does reduction involve?

The loss of oxygen

What is the term for the loss of electrons?

Oxidation

What is the term for the gain of electrons?

Reduction

When an acid reacts with metals what is formed?

A Salt and Hydrogen

What do we call a reaction where both oxidation and reduction are occurring?

Redox Reaction

What are acids neutralised by?

Alkalis and Bases

What is the general equation when an acid and alkali react?

Acid + Alkali makes Salt + Water

What is the general reaction when an acid and a metal carbonate react?

Acid + Metal carbonate makes Salt + Water + Carbon dioxide

Is a soluble metal hydroxide an alkali or a base?

Alkali

Is a metal oxide an alkali or a base?

Base

Is an insoluble metal hydroxide an alkali or a base?

Base

What type of salt does hydrochloric acid produce?

Chlorides

What type of salt does sulfuric acid produce?

Sulfates

What type of salt does nitric acid produce?

Nitrates

How can a salt solution produce solid salts

Crystallisation

What type of ions do acids produce in aqueous solutions?

H+

What type of ions do alkalis produce in aqueous solutions?

OH-

What is the range of the pH scale?

0-14

How can you measure the pH of a solution?

With universal indicator or a pH probe

What do we call a solution with a pH of 7?

Neutral

What do we call a solution with a pH of less than 7?

Acid

What do we call a solution with a pH greater than 7?

Alkali

In a neutralisation reaction the hydrogen ions react with hydroxide ions to make?

Water

What makes something a strong acid?

It is completely ionised in an aqueous solution

Give three examples of strong acids

Hydrochloric acid
Nitric acid
Sulfuric acid

What makes something a weak acid?

It is only partially ionised in an aqueous solution

Give three examples of weak acids

Ethanoic acid
Citric acid
Carbonic acid

For a given concentration, the stronger an acid, the \_____________ the pH?

Lower

As the pH decreases by one unit the hydrogen ion concentration of a solution increases by a factor of

10

When an ionic compound is melted or dissolved in water what can the ions do?

Move

What do we call solutions that can conduct electricity?

Electrolyte

What is the name of the negative electrode?

The Cathode

What is the name of the positive electrode?

The Anode

Ions are discharged at electrodes to produce

Elements

At which electrode is the metal produced?

The Cathode

At which electrode is the non metal produced?

The Anode

Electrolysis is used to extract metal if

It is too reactive to be extracted by reduction with Carbo

What is used to manufacture aluminium by electrolysis?

Aluminium oxide

What is added to aluminium oxide in the process of electrolysis?

Cyrolite

In the electrolysis of aluminium oxide what is the positive electrode made out of?

Carbon

When is hydrogen produced at the negative electrode in electrolysis?

When the metal is more reactive than Hydrogen

When is oxygen produced at the positive electrode in electrolysis?

When the solution does not contain a halide ion (halogen)

What type of reaction occurs at the cathode?

Reduction

What type of reaction occurs at the anode?

Oxidation

Complete this ionic equation 2H+ + 2e- makes

H2

What can be used to calculate the volumes of acids and alkalis?

Titrations

What units will be involved in titrations?

mol/dm3
g/dm3

What apparatus is required to measure volumes of one reactant to another

Burette

What is the name of the apparatus that accurately measure the volume of a reactant before transferring it to a conical flask

Pipette

What happens at the cathode during electrolysis?

Positive ions gain electrons (reduction)

What happens at the anode during electrolysis?

Negative ions lose electrons (oxidation)

Complete the half equation of the following:
2H+ + 2e- →

H2

Complete the half equation of the
following: 4OH- →

O2 + 2H2O + 4e