Acids, Bases and Salts (10)

How is sodium hydroxide manufactured in industries ? Name the process. In this process a gas X is formed as by-product. This gas reacts with lime

Dry hydrogen chloride gas does not change the colour of dry litmus paper. Why ?

Name the salt formed when sulphuric acid is added to sodium hydroxide and write its pH.

Dry HCl gas does not change the colour of dry blue litmus paper. Why?

Suggest a safe procedure of diluting a strong concentrated acid.

While electrolysing water before passing the current some drops of an acid are added. Why ? Name the gases liberated at cathode and anode. Write

The industrial process used for the manufacture of caustic soda involves electrolysis of an aqueous solution of compound ‘X’. In this process,

A student took a small amount of copper oxide in a conical flask and added dilute hydrochloric acid to it with constant stirring. He observed a

The name of the salt used to remove permanent hardness of water is:

1. Sodium hydrogen

 Sodium hydroxide is termed an alkali while Ferric hydroxide is not because:

1. Sodium

Acid present in tomato is:

1. Methanoic acid
2. Acetic acid
3. Lactic

When aqueous solutions of potassium iodide and lead nitrate are mixed, an insoluble substance separates out. The chemical equation for the

When Sodium bicarbonate reacts with dilute hydrochloric acid, the gas evolved is:

1. Hydrogen;

How do metal carbonates and metal hydrogen carbonates react with acids ? Taking magnesium as metal, write balanced chemical equations in both the

Copper utensils slowly lose their shiny brown surface and gain a green coat on prolonged exposure to atmospheric air. This is due to the

The acid produced in our stomach during digestion of food is

1. Hydrochloric

Which one of the following natural sources contains Oxalic acid ? 

When you add sodium hydrogen carbonate to acetic acid in a test tube, a gas liberates immediately with a brisk effervescence. Name this gas.

A student takes about 4 mL of distilled water in four test tubes marked P, Q, R and S. He then dissolves in each test tube an equal amount of one

What do we observe on pouring acetic acid on red and blue litmus papers ?

1. Red litmus remains

The pH of a salt used to make tasty and crispy pakoras is 14. Identify the salt and write a chemical equation for its formation. List its two

2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal taken in a test tube. When the contents are warmed, a gas

What is observed when a pinch of sodium hydrogen carbonate is added to 2 mL of acetic acid taken in a test tube ? Write chemical equation for the

A teacher provided acetic acid, water, lemon juice, aqueous solution of sodium hydrogen carbonate and sodium hydroxide to students in the school

While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid ?