Describe the reaction of zinc granules with dilute sulphuric acid with a diagram. Also, write the equation of zinc with sodium hydroxide.

When dilute sulphuric acid is reacted with zinc granules, then zinc being more reactive than hydrogen displaces it from the acid and forms zinc sulphate and hydrogen gas. Zn ( s ) + H 2 SO 4 ( dil ) → ZnSO 4 ( aq ) + H 2 ( g ) Zinc reacts with reacts with excess sodium hydroxide to form sodium zincate and hydrogen gas. Zn + 2 NaOH → Na 2 ZnO 2 + H 2 Sodium zincate At a temperature near 550 0 C , these reactions occur. The reaction is an example of endothermic reaction. Zn ( OH ) 2 + 2 NaOH → Na 2 ZnO 2 + 2 H 2 O

A solution of a substance "X" is used for whitewashing. (a) Name the substance "X" (b) Write the formula of substance "X" (c) Write the reaction of substance "X" with water

(a) Name of the substance is calcium oxide. The solution of the substance is used for whitewashing. It is also called quick lime or burnt lime. (b) The chemical formula is CaO . It is a binary compound. It contains calcium and oxygen (c) Quick lime reacts with water to form calcium hydroxide or slacked lime. It has many names including hydrated lime, caustic lime, slack lime, and pickling lime. CaO ( s ) + H 2 O ( l ) → Ca ( OH ) 2 ( aq )

Write the chemical equation for industrial production of dihydrogen gas and write its two uses.

Industrial production is mainly from steam reforming natural gas, and less often from more energy-intensive methods such as the electrolysis of water. Electrolysis of water is the process of using electricity to decompose water into oxygen and hydrogen gas by a process called electrolysis. 2 H 2 O ( l ) → 2 H 2 ( g ) + O 2 ( g ) Uses: 1. Hydrogen is used in the conversion of heavy fractions of petroleum into lighter fractions passing through hydrocracking. 2. It is also used in fuel cells for local electricity generation or as a transportation fuel.