Carbonates

Q.

Write the chemical equation to represent the ionic dissociation of sodium hydroxide in aqueous medium

Q. Write an equation for the reaction, when ammonium chloride and sodium hydroxide solution are mixed and heated.

Q.

Action of acids with carbonates and hydrogen carbonates:

(c) NaHCO₃ + H₂SO₄ 🡪

Q.

What happens when dilute hydrochloric acid is added to lead nitrate solution?

Q.

What happens when vinegar reacts with sodium carbonate

Q.

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

Q.

How will the action of dilute hydrochloric acid enable you to distinguish between the following :
(a) Sodium carbonate and sodium sulphite
(b) Sodium thiosulphate and sodium sulphite.

Q.

Example of :

acid +metal Bicarbonate -------> salt + water+ carbon dioxide

Q.

When conc. sulphuric acid is added to sodium chloride, sodium bisulphate and gas X is formed. If a rod dipped in ammonia is brought near gas X, dense white fumes of ammonium chloride are formed. What is X?

1. Carbon dioxide gas

2. Chlorine gas

3. Sulphur dioxide gas

4. Hydrogen chloride gas

Q.

Give three distinct tests [apart from using an indicator] you would carry out with solution of HC1 to illustrate the typical properties of an acid.

Q. Solution A is a sodium hydroxide solution. Solution B is a weak acid. C is dilute sulphuric acid. Which solution will
(i) liberate sulphur dioxide from sodium sulphite,
(ii) give a white precipitate with zinc sulphate solution,
(iii) contain solute molecules and ions?

Q.

What happens when hydrogen chloride gas is exposed to air?

1. Blue coloured precipitate is formed

2. White fumes of hydrochloric acid is formed

3. Black fumes are evolved

4. Red coloured precipitate is formed

Q.

In the reaction between $\mathrm{HCl}$ and ${\mathrm{Na}}_2{\mathrm{CO}}_3$, what gas is formed?

Q.

Distinguish between dilute sulphuric acid and dilute hydrochloric acid using barium chloride solution.

Q.

What happens when a cold and concentrated solution of sodium chloride reacts with ammonia and carbon dioxide? Write the chemical equation of the reaction which takes place.

Q.

Identify the anion present in each of the following compounds.

(i) A salt M on treatment with concentrated Sulphuric acid produces a gas which fumes in moist air gives dense fumes with Ammonia.

(ii) A salt D on treatment with dilute Sulphuric acid produces a gas which turns lime water milky but has no effect on acidified Potassium dichromate solution

(iii) When Barium chloride is added to salt solution E, a white precipitate insoluble in dilute Hydrochloric acid is obtained.

Q. (a) How is nitric acid prepared in laboratory?
(b) What is the purpose of conc. H₂SO₄ in the above preparation?
(c) Why is the temperature maintained at 200°C in the above reaction?
(d) Can we use conc. HCl in place of conc. H₂SO₄?

Q. Solution A reacts with an acid B(which gives greenish yellow gas on reacting with oxidising agents like Pb3O4) to give white precipitate C insoluble in nitric acid but soluble in ammonium hydroxide. Name A, B and C.

Q. Name the gas evolved when dilute hydrochloric acid is added to: [2 MARKS]
a) Calcium carbonate
b) Sodium sulphite

Q.

Why is commercial hydrochloric acid often in yellow color?

Q. Question 2
A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains:
1. NaCl
2. HCl
3. LiCl
4. KCl

Q.

Explain, why the following statement is not correct:
Lead chloride can be prepared by adding dilute HCl to lead sulphate solution.

Q.

STATE the characteristics of the chemical reaction which takes place when :

A) dil.hydrochloric acid is added to sodium carbonate

B) dil.sulphuric acid is added to barium chloride solution

C) wax is Burnes in the form of candle

Q.

Give reasons for the following:
(i) In the contact process, sulphur trioxide formed is dissolved in 98% sulphuric acid and not in water.
(ii) When solution of sulphur dioxide is exposed to air, it gets converted to sulphuric acid.
(iii) When diluting concentrated sulphuric acid, the acid should be added to water and not water to the acid.
(iv) When concentrated sulphuric acid is exposed to air, its volume increases and it becomes slightly dilute.
(v) Sulphuric acid can form two kinds of salts with sodium chloride.
(vi) When barium chloride is added to dilute sulphuric acid, a white precipitate is formed.
(vii) When carbon is heated with concentrated sulphuric acid, carbon dioxide is formed.
(viii) Ammonia gas cannot be dried by passing through concentrated sulphuric acid.
(ix) When concentrated sulphuric acid is added to sugar/glucose, a black mass is left behind.
(x) Concentrated sulphuric acid should not be added to oxalic acid or formic acid in the open laboratory.
(xi) When concentrated sulphuric acid is added to blue crystalline copper sulphate, it turns powdery white.
(xii) Concentrated sulphuric acid must be stored in airtight bottles.
(xiii) Cotton clothes get burnt with concentrated sulphuric acid.
(xiv) H₂SO₄ cannot be prepared by heating sodium sulphate with conc. HCl or HNO₃.

Q.

What would you observe in the following cases?
(i) Sulphur trioxide is dissolved in water on a large scale.
(ii) Concentrated sulphuric acid is added to equal volumes of cold water.
(iii) 100 ml of 98% sulphuric acid is kept open.
(iv) Hot concentrated sulphuric acid is added to sodium chloride crystals.
(v) Dilute sulphuric acid is added to ferrous sulphate solution.

Q. In the laboratory carbon dioxide is prepared by:

1. reacting an acid and a carbonate
2. heating a carbonate
3. burning carbonaceous materials
4. fermentation
   

Q.

Which of the following gas is prepared by warming ammonium sulphate with slaked lime?

1. Hydrogen

2. Nitrogen

3. Hydrogen chloride

4. Ammonia

Q.

Fill in the blanks:
(i) Aqua-regia is a mixture of _________.
(ii) A constant boiling mixture of water and hydrochloric acid is also called as _________.
(iii) ________ agent converts hydrochloric acid to chlorine.
(iv) Hydrogen and chlorine reacts in presence of _________ to form hydrogen chloride.
(v) On addition of silver nitrate to hydrochloric acid ________ precipitate is formed which is soluble in __________.
(vi) The white precipitate of lead chloride is soluble in __________.

Q.

1.Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCL) is added to test tube A , while acetic acid (CH₃COOH) is added to test tube B.In which test tube will the fizzing occur more vigorously and why?

Q.

Carbon dioxide gas is liberated when $HCl$ acid is added to:

1. Lead Nitrate.

2. Sodium Nitrate.

3. Silver Chloride.

4. Calcium Carbonate.