Hydrogen Test

Result

Hydrogen Test - 8

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

D₂O differs from H₂O in many of its physical properties because of the isotope effect. Which of the following options regarding the properties of D₂O and H₂O is incorrect?

A
D₂O has a higher melting point than H₂O.

B
D₂O has a smaller dissociation constant than H₂O.

C
D₂O has a higher boiling point than H₂O.

D
D₂O has a lesser density than H₂O.

Solution

D₂O has a greater molecular mass (20 u) than H₂O (18 u), and hence, a greater mass density.
Question 2
1 / -0

Which of the following statements regarding the laboratory preparation of hydrogen by reacting zinc granules with dilute sulphuric acid is false?

Zn (s) + H₂SO₄(dil.) → ZnSO₄(aq) + H₂(g)

A
The reaction may be categorised as a redox reaction.

B
Sulphuric acid is the oxidising agent in the reaction.

C
Pure Zn metal is used to increase the yield of the product as well as the rate of the reaction.

D
The gas formed may be tested by bringing a burning candle near the mouth of the test tube.

Solution

Statement (3) is incorrect as pure zinc metal reacts very slowly with dilute acids. On the contrary, the presence of impurities speeds up the process by forming electrochemical couples.
Question 3
1 / -0

Which of the following processes is used to prepare very pure hydrogen?

A
Lane's Process

B
Uyeno's Proces

C
Bosch process

D
Water gas shift reaction

Solution

Uyeno's method of reacting KOH with scrap aluminium yields pure hydrogen.

2Al + 2KOH + 2H₂O → 2KAlO₂ + 3H₂

Very pure hydrogen (99.9%) is prepared by the action of water on salt hydrides (e.g. NaH).

NaH + H₂O → NaOH + H₂
Question 4
1 / -0

Which pair of compounds reacts with water to liberate azane gas?

A
(NH₄)₂SO₄ and Ca(CN)₂

B
Mg₃N₂ and Ca(CN)₂

C
Mg₃N₂ and (NH₄)₂SO₄

D
Ca₃N₂ and CaCN₂

Solution

Ammonia is also known as azane.
Nitrides and cyanides react with water to liberate ammonia.
Ca₃N₂ + 6H₂O → 3Ca(OH)₂ + 2NH₃
CaCN₂ + 3H₂O → CaCO₃ + 2NH₃
Question 5
1 / -0

Which of the following compounds is used for water softening?

A
Ca₃(PO₄)₂

B
Na₃PO₄

C
Na₆P₆O₁₈

D
Na₂HPO₄

Solution

Polyphosphates, such as sodium hexametaphosphate, combine with cations (Ca²⁺ or Mg²⁺) to form soluble complexes.

2Ca²⁺ + Na₂[Na₄(PO₃)₆] → 4Na⁺ + Na₂[Ca₂(PO₃)₆]
Question 6
1 / -0

Which of the following is used for restoring the exhausted "Permutit"?

A
10% HCl solution

B
10% NaCl solution

C
10% MgCl₂ solution

D
10% BaCl₂ solution

Solution

The exhausted zeolite may be regenerated by passing 10% solution of sodium chloride through it. The following reactions take place:
CaZ + 2Na⁺ → Na₂Z + Ca²⁺
(exhaused (regenerated
Zeolite) zeolite)
MgZ + 2Na⁺ → Na₂Z + Mg²⁺
The regenerated sodium zeolite can be used again for softening of water.
Question 7
1 / -0

When a zeolite, which is hydrated sodium aluminium silicate, is treated with hard water, the sodium ions are exchanged with

A
Ca²⁺ and Mg²⁺

B
OH^-

C
SO₃^2-

D
H⁺

Solution

Na₂Al₂Si₂O₈.xH₂O is written as Na₂Z, Na⁺ ions exchange Ca²⁺ and Mg²⁺ ions in hard water.

Na₂Z + Mg²⁺ → 2Na⁺ + MgZ

Na₂Z + Ca²⁺ → 2Na⁺ + CaZ

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Hydrogen Test - 8

Result

Hydrogen Test - 8

Score

-

Rank

-

SHARING IS CARING

Question 1

D2O has a higher melting point than H2O.

D2O has a smaller dissociation constant than H2O.

D2O has a higher boiling point than H2O.

D2O has a lesser density than H2O.

Solution

Question 2

The reaction may be categorised as a redox reaction.

Sulphuric acid is the oxidising agent in the reaction.

Pure Zn metal is used to increase the yield of the product as well as the rate of the reaction.

The gas formed may be tested by bringing a burning candle near the mouth of the test tube.

Solution

Question 3

Lane's Process

Uyeno's Proces

Bosch process

Water gas shift reaction

Solution

Question 4

(NH4)2 SO4 and Ca(CN)2

Mg3N2 and Ca(CN)2

Mg3N2 and (NH4)2SO4

Ca3N2 and CaCN2

Solution

Question 5

Ca3(PO4)2

Na3PO4

Na6P6O18

Na2HPO4

Solution

Question 6

10% HCl solution

10% NaCl solution

10% MgCl2 solution

10% BaCl2 solution

Solution

Question 7

Ca2+ and Mg2+

OH-

SO32-

H+

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.

D₂O has a higher melting point than H₂O.

D₂O has a smaller dissociation constant than H₂O.

D₂O has a higher boiling point than H₂O.

D₂O has a lesser density than H₂O.

(NH₄)₂SO₄ and Ca(CN)₂

Mg₃N₂ and Ca(CN)₂

Mg₃N₂ and (NH₄)₂SO₄

Ca₃N₂ and CaCN₂

Ca₃(PO₄)₂

Na₃PO₄

Na₆P₆O₁₈

Na₂HPO₄

10% MgCl₂ solution

10% BaCl₂ solution

Ca²⁺ and Mg²⁺

OH^-

SO₃^2-

H⁺