Science : Ch 01 – Chemical Reactions and Equations

Which reaction takes place when layer of silver deposit on copper wire when dipped in silver nitrate solution?

Give an example of decomposition reaction taking place in our body.

When hydrogen sulphide gas is passed through a blue solution of copper sulphate, the colour of the solution fades and a black precipitate is obtained.Name the type of reaction taking place.

When hydrogen sulphide gas is passed through a blue solution of copper sulphate, the colour of the solution fades and a black precipitate is obtained.Write the chemical name of the black precipitate formed.

Mention whether it is physical or chemical changes:- Burning of Liquefied Petroleum Gas (LPG)

Mention whether it is physical or chemical changes :Curdling of milk

In the electrolysis of water, name the gases liberated at anode

On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper oxide (black), oxygen gas and a brown gas X is formed. Identify the brown gas X evolved.

Solid calcium oxide reacts vigorously with water to form calcium hydroxide, accompanied by liberation of heat. This process is called slaking of lime. Calcium hydroxide dissolves in water to form a solution called lime water. Which among the following is (are) true about slaking of lime and the solution formed?

1. It is an endothermic reaction
2. It is an exothermic reaction.
3. The pH of the resulting solution will be more than seven.
4. The pH of the resulting solution will be less than seven

Strong heating of ferrous sulphate leads to the formation of a brown solid and two gases. This reaction can be designated as:

Which of the following reactions is an endothermic reaction?

The following reaction is used for the preparation of oxygen gas in the laboratory: 2KClO₃(s) Heat ⎯ → Catalyst ⎯⎯⎯ 2KCl(s) + 3O₂(g) Which of the following statement(s) is/are correct about the reaction?

Which of the subsequent does show an oxidation reaction

Calcium oxide reacts vigorously with water to produce slaked lime. CaO(s) + H₂O(l) → Ca(OH)₂(aq) This reaction can be classified as:

1. Combination reaction
2. Exothermic reaction
3. Endothermic reaction
4. Oxidation reaction

The following reaction is an example of a: 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g)

1. Displacement reaction
2. Combination reaction
3. Redox reaction
4. Neutralisation reaction