Advertisements
Advertisements
Question
State an important use of decomposition reactions.
Advertisements
Solution
“An important use of decomposition reactions is in the extraction of metals from their naturally occurring compounds like chlorides or oxides.”
For Example:
When electricity is passed through molten sodium chloride, it decomposes to give pure sodium metal at the cathode.
\[\ce{\underset{(molten)}{2NaCl} ->[Electricity] \underset{(Metal)}{2Na} + Cl2_{(g)}}\]
APPEARS IN
RELATED QUESTIONS
Write the balanced chemical equation for the following and identify the type of reaction.
\[\ce{Zinc carbonate(s) -> Zinc oxide(s) + Carbon dioxide(g)}\]
What does one mean by exothermic reaction? Give example.
Decomposition reactions require energy either in the form of heat or light or electricity for breaking down the reactants. Write one equation each for decomposition reactions where energy is supplied in the form of heat, light and electricity
Rewrite the following statements by selecting the correct options:
\[\ce{CaCO3 ->[\Delta] CaO + CO2 ^}\] is a __________ reaction.
Give one example of a decomposition reaction which is carried out by applying heat.
Two metals X and Y form the salts XSO4 and Y2SO4, respectively. The solution of salt XSO4 is blue in colour whereas that of Y2SO4 is colourless. When barium chloride solution is added to XSO4 solution, then a white precipitate Z is formed along with a salt which turns the solution green. And when barium chloride solution is added to Y2SO4 solution, then the same white precipitate Z is formed along with colourless common salt solution.
- What could the metals X and Y be?
- Write the name and formula of salt XSO4.
- Write the name and formula of salt Y2SO4.
- What is the name and formula of white precipitate Z?
- Write the name and formula of the salt which turns the solution green in the first case.
Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.
\[\ce{Zn_{(s)} + H2SO4 -> ZnSO4_{(s)} + H2_{(g)}}\]
Give a scientific reason.
When the gas formed on heating limestone is passed through freshly prepared lime water, the lime water turns milky.
A student wants to study a decomposition reaction by taking ferrous sulphate crystals. Write two precautions he must observe while performing the experiment.
Give a balanced equation for –
A white precipitate obtained during a double decomposition reaction involving a silver salt with sodium salt.
Give a balanced equation for the following type of reaction:
A thermal decomposition reaction in which a compound decomposes to give two new compounds.
Differentiate between the following:
Thermal decomposition and thermal dissociation.
What is electrolysis?
The following reaction is used for the preparation of oxygen gas in the laboratory:
\[\ce{2KClO3_{(s)} ->[Heat] 2KCl + 3O2_{(g)}}\]
Which of the following statement about the reaction is correct?
Which one of the following processes involves chemical reactions?
Give the ratio in which hydrogen and oxygen are present in water by volume.
When SO2 gas is passed through a saturated solution of H2S, which of the following reaction occurs?
A metal nitrate 'A' on heating gives a metal oxide along with evolution of a brown coloured gas 'B' and a colourless gas, which helps in burning. Aqueous solution of 'A' when reacted with potassium iodide forms a yellow precipitate.
- Identify 'A' and 'B'
- Name the types of the reactions involved in the above statement.
Write one equation for the decomposition reaction where energy is supplied in the form of light.
