Chapter 1 – Chemical Reactions and Equations

What happens when dilute hydrochloric acid is added to iron filling? Tick the correct answer

Assertion: A lead nitrate on thermal decomposition gives lead oxide, brown coloured nitrogen dioxide and oxygen gas.
Reason: Lead nitrate reacts with potassium iodide to form yellow ppt of lead iodide and the reaction is double displacement as well as precipitation reaction.

The reaction between lead nitrate and potassium iodide present in aqueous solutions is an example of

The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called:

The reaction between lead nitrate and potassium iodide present in aqueous solutions is an example of

Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is:

What type of chemical reactions take place when electricity is passed through water?

Which of the following is an endothermic process?

Oxidation is a process which involves

Give the ratio in which hydrogen and oxygen are present in water by volume.

A substance which oxidizes itself and reduces other is known as

In an electrolytic cell where electrolysis is carried, anode has:

Which of the following reactions is not correct:

Copper displaces which of the following metals from its salt solution:

Which of the following involves combination of two elements?

Some crystals of copper sulphate were dissolved in water. The colour of the solution obtained would be:

When dilute HCl is added to zinc pieces taken in a test tube

Magnesium ribbon is rubbed before burning because it has a coating of:

Which one of the following processes involve chemical reactions?

Assertion: Zinc reacts with sulphuric acid to form zinc sulphate and hydrogen gas and it is displacement reaction.
Reason: Zinc reacts with oxygen to form zinc oxide.

Assertion: MnO2 + 4HCl → MnCl2 + Cl2 + 2H2O is redox reaction.Reason: MnO2 oxides HCl to Cl2 and gets reduced to MnCl.

Assertion: Magnesium ribbon keeps on burning in atmosphere of nitrogen.
Reason: Magnesium reacts with nitrogen to form magnesium nitrides and this reaction is combination reaction.

Heat is evolved during:

Dissolving suger is an example of

A substance added to food containing fats and oils is called:

Select the oxidising agent for the following reaction:
H2S + I2 > 2HI + S

A substance ‘X’ is used in white-washing and is obtained by heating limestone in the absence of air. Identify ‘X’.

The process of reduction involves

Which of the following gases can be used for storage

Pb + CuCl2 → PbCl2 + Cu
This reaction is an example of: