Direct Combination

Q. (i) phosphorus burns in presence of chlorine to form phosphorus pentachloride.

Q.

How does hydrogen react with chlorine gas?

Q. The heat of neutralization of LiOH and HCL at 25^°C is 34.868 kJ mol`1(mole inverse).The heat of ionisation of LiOH will be

Q. Name the kind of particle present in
sodium hydroxide solution
Carbonic acid
Sugar solution

Q. Explain the following: [5 MARKS]
(a) Thick white fumes are formed when a glass rod dipped in $N{H}_{4}OH$ is brought near the mouth of a bottle full of HCl gas.
(b) Dry Hydrogen chloride gas does not affect a dry strip of blue litmus but turns red in the presence of a drop of water.
(c) Hydrogen Chloride gas is not collected over water.

Q. What is the freezing pt of solution containing 8.1gHBr in 100g water assuming the acid to be 90% ionised?(Kf for HBr is1.86K/mol)

Q. What helps Diammine silver chloride to make silver chloride soluble in ammonium hydroxide???

Q.

Why is direct sunlight not used in the preparation of hydrogen chloride gas?

1. Reaction is explosive in direct sunlight.

2. Reaction is slow in direct sunlight.

3. There is no reaction in direct sunlight.

4. Reaction is uncontrollable in direct sunlight.

Q.

Hydrogen is used in the manufacture of hydrochloric acid.

1. True
2. False

Q. 0.001 mole of Cr(NH3)5(NO3)SO4 was passed through cation exchanger and the acid coming out of it required 20 ml 0.1M NaOH for neutralisation. Hence the complex is ?

Q. Name the drying agent used for laboratory preparing of hydrogen chloride gas.

Q.

Identify the gas evolved in the following reactions when:
Concentrated hydrochloric acid is made to react with manganese dioxide.

Q. State the safety precaution you would take for the preparation hydrochloric acid.

Q.

Hydrogen chloride gas being highly soluble in water is dried by:

1. Concentrated sulphuric acid

2. Calcium carbonate

3. Quick lime

4. Phosphorous pentaoxide

Q. During the preparation of hydrogen chloride gas on a humid day, the gas is usually passed through the guard tube containing calcium chloride. The role of calcium chloride taken in the guard tube is to :

1. absorb the evolved gas
2. absorb moisture from the gas
3. absorb Cl${}^{-}$ ions from the evolved gas
4. moisten the gas

Q.

The nature of the reaction of combining moist hydrogen gas with chlorine in direct sunlight is

1. Slow

2. Controlled

3. The reaction will not carry out in sunlight.

4. Explosive

Q. During the preparation of hydrogen chloride gas on a humid day. the gas is usually passed through the guard tube containing anhydrous calcium chloride. The role of anhydrous calcium chloride taken in the guard tube is to:

1. absorb the evolved gas
2. moisten the gas
3. absorb moisture from the gas
4. absorb $C{l}^{-}$ ions from the evolved gas

Q. Write the equation for its laboratory preparing of hydrogen chloride gas mentioning the condition required.

Q. What is the reaction between hydrogen and chlorine?

Q. The reaction of moist hydrogen gas with chlorine is explosive in the presence of :

1. hydrogen
2. oxygen
3. darkness
4. direct sunlight

Q. Name some gases which can be prepared in Kipp’s apparatus.[2 Marks]

Q. Dry hydrogen chloride gas can be collected by ____________ displacement of air.

1. upward
2. downward
3. sideward
4. parellel

Q.

1. True
2. False

Q.

Name the gas evolved in each case (the formula is not acceptable).

The gas produced by the action of concentrated sulphuric acid on sodium chloride.

Q. Equal volumes of hydrogen and chloride are exposed to diffused sunlight to prepare

1. hydrogen chloride
2. sodium hydroxide
3. water
4. hydrochloric acid

Q. Assertion: when NaOH is added to the HCl solution, the conductance of the solution decreases right upto the equivalence point and then increases.
Reason: At starting, fast moving to ions replaced by relatively slower moving $N{a}^{\oplus }$ ions and after the equivalence point, as $O{H}^{-}$ start increases conductance increases.

1. Statement 1 & 2 are correct and statement 2 is correct explanation of statement 1
2. Statement 1 & 2 are correct but statement 2 is not correct explanation of statement 1
3. Statement 1 is true, statement 2 is false
4. Statement 1 is false and statement 2 is true

Q.

Give one example each of the following:

Normal salt

Q. Metal chloride + Sulphuric acid$⟶$.............. + Hydrogen chloride :

1. Metallic sulphate
2. Metallic bisulphate
3. Metallic sulphide
4. None of the above

Q. In the laboratory preparation of $HCl$, which of the following are preferred?

1. Conc. $H_{2}S{O}_4$ as reactant
2. Conc. $H_{2}S{O}_4$ as drying agent
3. Temperature of reaction mixture below ${200}^{0}C$
4. Use of activated carbon as catalyst

Q. Moist hydrogen gas combines with chlorine in the presence of diffused sunlight to form $HCl$. The catalyst used here is :

1. oxygen.
2. silica.
3. moisture.
4. alum.