Question

Define neutralization. Explain with the help of an example.

5. List any three changes that take place during a chemical change.

6. Explain how crystals of copper sulphate are formed.​

Answer 1

The reaction between an acid and a base is known as neutralization. Salt and water are produced in this process with the evolution of heat.

Example:

HCl+NaOH⟶NaCl+H2O

Three changes that take place during chemical reaction are -

1. change of state

2. change of temperature

3. formation of precitate

Crystallization is the process by which we can obtain crystals of copper sulphate. In this process, a few drops of dilute sulphuric acid is added to water. The water is then boiled & as it starts boiling, copper sulphate powder is added with stirring. The powder must be added on till the solution becomes saturated.

Answer 2

Answer:

A neutralization reaction is when an acid and a base react to form water and a salt. For example, when hydrochloric acid(acid) and sodium hydroxide(base) react they form sodium chloride(salt) and water. Also, heat is evolved.

5. Three changes that take place during a chemical change are:

• Change of color (for example, silver to reddish-brown when iron rusts).
• Change in temperature or energy, such as the production (exothermic) or loss (endothermic) of heat
• Change of composition - paper turning to ash when burned.

6. Crystallization is the process by which we can obtain crystals of copper sulphate. In this process, a few drops of dilute sulphuric acid is added to water. The water is then boiled & as it starts boiling, copper sulphate powder is added with stirring. The powder must be added on till the solution becomes saturated. Afterwards, it is filtered into a china dish and allowed to cool, undisturbed. After some time the crystals of copper sulphate separate out.

Hope it helps you