What are the indicators? Give two examples each of natural and artificial indicators.

Write the common name of CaOCl₂.

Name the gas evolved when NaOH reacts with zinc.

Why are toothpaste basic in nature?

Name the acid present in an ant sting.

An aqueous solution of an acid conducts electricity. Give reason.

Effervescences are formed when the batter for cake is heated. Which substance is present in batter?

What is a universal indicator? Give its use.

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

Write the name and formula of each or the following

(a) an acidic salt

(b) a basic salt.

Justify the statement ‘plants and animals are pH sensitive’ by giving two examples.

What are the products formed when an acid reacts with a base? What is the type of reaction? Give one example and name the salt obtained.

Identify the compound X on the basis of the reactions given below. Also, write the name and chemical formulae of A, B and C.

A gas X reacts with lime water and forms compound Y which is used as a bleaching agent in chemical industry. Identify X and Y. Give the chemical equation of the reaction involved.

a. A solution has a pH of 7 (seven). Explain how you would

i. increase its pH

ii. decease its pH

(b) What can you say about the pH of a solution that liberate CO₂ from sodium carbonate? Write the balanced chemical equation for the reaction.

Fill in the missing data in the given table:

You are provided with three test tubes A, B, C which contain distilled water, acidic and basic solutions. If you are given blue litmus paper only, how will you identify the nature of the solutions in three test tubes?

How will you prove that a given salt is a carbonate of a metal?

For each of the compound A and B, suggest a suitable method its preparation along with the balanced chemical equations.

i. A is bleaching powder

ii. B is gypsum

Mention two uses of bleaching powder.

A compound ‘X’ is bitter to taste. It is compound of washing powder and reacts with dilute HCl to produce brisk effervescence due to a colourless and odourless gas ‘Y’ which turns lime water milky due to the formation of ‘Z’ when an excess of CO₂ is passed, milkiness disappears due to the formation of ‘P’. Identify ‘X’. ‘Y’, ‘Z’ and ‘P’. Write the equations involved in the formation of Y, Z, and P.

For making the cake, baking powder is taken. If at home your mother uses baking soda instead of baking powder in the cake.

(a) How will it affect the taste of the cake and why?

(b) How can baking soda be converted into baking powder?

(c) What is the role of tartaric acid added to the baking soda?