Class 10 ch 2

HCl has pH 7.1 .

• Yes

• No

Some fruits like mango,lemon, rawgrapes, orange has sour taste dur to the presence of

• Acetic acid

• Citric acid

• Lactic acid

• Oxalic acid

Brine is an:

• Aqueous solution of sodium hydroxide

• Aqueous solution of sodium carbonate

• Aqueous solution of sodium chloride

• Aqueous solution of sodium bicarbonate

Zinc granules on treating with an acid X, form the zinc sulphate (ZnSO4) salt along with the evolution of a gas Y which burns with a pop sound when brought near to a burning candle. Identify the acid X and gas evolved Y.

• X- Sulphuric acid and Y- Oxygen gas

• X- Hydrochloric acid and Y- Oxygen gas

• X- Sulphuric acid and Y- Hydrogen gas

• X- Hydrochloric acid and Y- Hydrogen gas

The figure given below represents the experiment carried out between concentrated sulphuric acid and sodium chloride, which react with each other to form HCl gas.

Blue litmus paper is brought near the mouth of the delivery tube to check the presence of HCl acid but no change is observed in the color of litmus paper because:

• The litmus paper used is moist

• The litmus paper used is dry

• Blue litmus paper does not change its color with an acid

• The litmus paper is kept very close to the mouth of the delivery tube

Dilute acid does not produce carbon dioxide on being treated with:

• Marble

• Lime

• Baking soda

• Limestone

Identify the products of the following reaction:

• Calcium hydrogencarbonate and chlorine gas

• Calcium chloride and water

• Calcium oxide, carbon dioxide and water

• Calcium chloride, carbon dioxide and water

In the following reaction, identify the salt formed

NH₄OH (aq) + H₂SO₄ (aq) → _____ + 2H₂O (l)

• NH₄NO₃

• (NH₄)₂SO₄

• (NH₄)₃PO₄

• (NH₄)₂S

What is the chemical name of 'plaster of paris'?

Copper sulphate crystals when heated strongly, lose their water of crystallization to give anhydrous copper sulphate accompanied by a change in color from:

• Blue to green

• Blue to red

• Blue to grey

• None