An acid which can decolourise purple coloured potassium permanganate solution is:
sulphuric acid
citric acid
carbonic acid
hydrochloric acid
In the equation
NaOH + HNO3 → NaNO3 + H2O nitric acid is acting as
An oxidising agent
An acid
A nitrating agent
A dehydrating agent
When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution. The reaction is an example of
A combination reaction
A displacement reaction
A decomposition reaction
A double decomposition reaction
When lead nitrate is heated, it breaks down into lead monoxide, nitrogen dioxide and oxygen.
2Pb(NO3)2 → 2PbO + 4NO2 + O2
The reaction is an example of
Combination reaction
Decomposition reaction
Double decomposition reaction
Displacement reaction
When the gases sulphur dioxide and hydrogen sulphide mix in the presence of water, the reaction
SO2 + 2H2S → 2H2O + 3S occurs.
Here, hydrogen sulphide is acting as
A reducing agent
A catalyst
The reaction 2Na + Cl2 → 2NaCl is an example of
The chemical reaction between quicklime and water is characterised by:
evolution of hydrogen gas
formation of slaked lime precipitate
change in temperature of mixture
change in colour of the product
Oil and fat containing items are flushed with nitrogen for preventing
Burning
Rancidity
Neutralisation
Rusting
The chemical equations are balanced to satisfy one of the following laws in chemical reactions. This law is known as:
law of conservation of momentum
law of conservation of mass
law of conservation of motion
law of conservation of magnetism
Fe2O3 + 2Al → Al2O3 + 2Fe
The above reaction is an example of a
Double displacement reaction
