GCSE CHEMISTRY ELECTROLYSIS EXAM REVISION QUESTIONS
WITH VERIFIED SOLUTIONS LATEST 2025 UPDATE.
What is electrolysis? - ANSWER- Electrolysis is the process by which ionic substances are
decomposed (broken down) into simpler substances when an electric current is passed through
them. During electrolysis, metals and gases may form at the electrodes. To understand electrolysis,
you need to know what an ionic substance is.
How are ionic substances formed? - ANSWER- Ionic substances form when a metal reacts with
a non-metal. They contain charged particles called ions. For example, sodium chloride forms when
sodium reacts with chlorine. It contains positively charged sodium ions and negatively charged
chloride ions. Ionic substances can be broken down by electricity.
What is needed for electrolysis to work? - ANSWER- For electrolysis to work, the ions must
be free to move. Ions are free to move when an ionic substance is dissolved in water or molten
(melted). For example, if electricity is passed through copper chloride solution, the copper chloride
is broken down to form copper metal and chlorine gas.
What happens during electrolysis? - ANSWER- 1. Positively charged ions move to the negative
electrode during electrolysis. They receive electrons and are reduced.
2. Negatively charged ions move to the positive electrode during electrolysis. They lose electrons
and are oxidised.
, How do you predict to product of electrolysis? - ANSWER- Ionic substances in solution break
down into elements during electrolysis. Different elements are released depending on the particular
ionic substance.
What happens at the negative electrode (cathode)? - ANSWER- At the negative electrode,
positively charged ions gain electrons. This is reduction, and you say that the ions have been
reduced.
Metal ions and hydrogen ions are positively charged. Whether you get the metal or hydrogen
during electrolysis depends on the position of the metal in the reactivity series:
1. the metal will be produced if it is less reactive than hydrogen
2. hydrogen will be produced if the metal is more reactive than hydrogen
Why does the reactivity series affect electrolysis? - ANSWER- The reactivity series of metal -
carbon and hydrogen are not metals, but they are shown for comparison
So the electrolysis of copper chloride solution produces copper at the negative electrode. But the
electrolysis of sodium chloride solution produces hydrogen.
What is the reactivity series? - ANSWER- Potassium K Most Reactive
Sodium Na
Calcium Ca
Magnesium Mg
Aluminium Al
Carbon C
Zinc Zn
WITH VERIFIED SOLUTIONS LATEST 2025 UPDATE.
What is electrolysis? - ANSWER- Electrolysis is the process by which ionic substances are
decomposed (broken down) into simpler substances when an electric current is passed through
them. During electrolysis, metals and gases may form at the electrodes. To understand electrolysis,
you need to know what an ionic substance is.
How are ionic substances formed? - ANSWER- Ionic substances form when a metal reacts with
a non-metal. They contain charged particles called ions. For example, sodium chloride forms when
sodium reacts with chlorine. It contains positively charged sodium ions and negatively charged
chloride ions. Ionic substances can be broken down by electricity.
What is needed for electrolysis to work? - ANSWER- For electrolysis to work, the ions must
be free to move. Ions are free to move when an ionic substance is dissolved in water or molten
(melted). For example, if electricity is passed through copper chloride solution, the copper chloride
is broken down to form copper metal and chlorine gas.
What happens during electrolysis? - ANSWER- 1. Positively charged ions move to the negative
electrode during electrolysis. They receive electrons and are reduced.
2. Negatively charged ions move to the positive electrode during electrolysis. They lose electrons
and are oxidised.
, How do you predict to product of electrolysis? - ANSWER- Ionic substances in solution break
down into elements during electrolysis. Different elements are released depending on the particular
ionic substance.
What happens at the negative electrode (cathode)? - ANSWER- At the negative electrode,
positively charged ions gain electrons. This is reduction, and you say that the ions have been
reduced.
Metal ions and hydrogen ions are positively charged. Whether you get the metal or hydrogen
during electrolysis depends on the position of the metal in the reactivity series:
1. the metal will be produced if it is less reactive than hydrogen
2. hydrogen will be produced if the metal is more reactive than hydrogen
Why does the reactivity series affect electrolysis? - ANSWER- The reactivity series of metal -
carbon and hydrogen are not metals, but they are shown for comparison
So the electrolysis of copper chloride solution produces copper at the negative electrode. But the
electrolysis of sodium chloride solution produces hydrogen.
What is the reactivity series? - ANSWER- Potassium K Most Reactive
Sodium Na
Calcium Ca
Magnesium Mg
Aluminium Al
Carbon C
Zinc Zn
