In lab $$H _ { 2 } \mathrm { O } _ { 2 }$$ is prepared by

cold $$H_{2} S O _ { 4 } + B a O _ { 2 }$$

$$\mathrm { Conc } . \mathrm { H } _ { 2 } \mathrm { SO } _ { 4 } + \mathrm { Na } _ { 2 } \mathrm { O } _ { 2 }$$

In the laboratory $$H_2O_2$$ is prepared by the action of :

cold dilute $$H_2SO_4$$ on hydrated $$BaO_2$$

neither electropositive nor electronegative

MCQ Questions for Class 11 Medical Chemistry Hydrogen Quiz 9

H^{+}

$H^+$ in acid medium is balanced by which of the following species

0%
$O{H^ - }$
0%
${H_2O }$
0%
${H_2}$
0%
${H_2}^ +$

Water gas is a mixture of

0%
carbon monoxide and oxygen
0%
carbon monoxide and hydrogen
0%
hydrogen and oxygen
0%
hydrogen and nitrogen

Explanation

Water gas is a mixture of carbon monoxide and hydrogen produced from synthesis gas. Synthesis gas is a useful product, but requires careful handling due to its flammability and the risk of carbon monoxide poisoning. The water-gas shift reaction can be used to reduce the carbon monoxide while producing additional hydrogen, resulting in water gas.

Synthesis gas is made by passing steam over a red-hot carbon fuel such as coke:

H_{2} O + C \to H_{2} + C O; (Δ H = + 131 k J / m o l)

${\ {{H_2O}+C\rightarrow {H_2}+CO; \quad \quad (\Delta {\mathit {H}}=+131kJ/mol)}}$

The reaction is endothermic, so the fuel must be continually re-heated to keep the reaction going. In order to do this, an air stream, which alternates with the vapor stream, is introduced for the combustion of carbon to take place.

O_{2} + C \to C O_{2} (Δ H = - 393 k J / m o l)

${ {O_2{}+C\rightarrow CO_2\quad \quad \ (\Delta {\mathit {H}}=-393kJ/mol)}}$

Theoretically, to make 6 L of water gas, 5 L of air is required.

Or, alternatively, to prevent contamination with nitrogen, energy can be provided by using pure oxygen to burn carbon into carbon monoxide.

O_{2} + 2 C \to 2 C O (Δ H = - 221 k J / m o l)

${ {O_2{}+2C \rightarrow2CO\quad \quad \ (\Delta {\mathit {H}}=-221kJ/mol)}}$

In this case 1 L of oxygen will create 5.3 L of pure water gas.

Hence, the correct option is

B

$\text{B}$

Which of the following ions have highest ionic density?

0%
$H^{+}$
0%
$Li^{+}$
0%
$Na^{+}$
0%
$K^{+}$

The correct statements among (a) to (d) regarding H

_{2}

$_2$ as a fuel are :

(a) It produces less pollutant than petrol.

(b) A cylinder of compressed dihydrogen weighs

\sim 30

$\sim 30$ times more than a petrol tank producing the same amount of energy.

N a N i_{5}

$NaNi_5$

(d) On combustion, values of energy released per gram of liquid dihydrogen and LPG are 50 and 142 kJ, respectively

0%
b and d only
0%
a, b and c only
0%
b, c and d only
0%
a and c only

Explanation

(a)

H_{2}

$H_2$ produces less pollution as compared to petrol because on combustion it does not produce carbon mono oxide.

(b) A cylinder of compressed dihydrogen weighs 30 times more than a petrol tank producing the same amount of energy. It has higher calorific value.

(d) On combustion, the value of energy released per gram of liquid dihydrogen is 142 kJ.

So, B option is correct.

In which of the following properties listed below, hydrogen does not show similarity with halogens?

0%
Nature of the oxide
0%
Electropositive character
0%
Combination with alkali metals
0%
Atomicity

NaH is an example of :

0%
Electron-rich hydride
0%
Molecular hydride
0%
Saline hydride
0%
Metallic hydride

Why are the following metals not used in the lab preparation of hydrogen ?

0%
calcium
0%
iron
0%
aluminium
0%
sodium

Decomposition of

H_{2} O_{2}

$H_{2}O_{2}$ can be prevented by addition of

0%
Acetanilide
0%
Benzene
0%
Alkali metal oxide
0%
$MnO_{2}$

Explanation

Solution:- (A) Acitanilide

The decomposition of

H_{2} O_{2}

${H}_{2}{O}_{2}$ can be prevented by the addition of little

H_{3} P O_{4}

${H}_{3}P{O}_{4}$ , glycerine, acetanilide, alcohol, etc. which can act as negative catalyst or inhibitors.

The hydride that is not electron deficent is:

0%
$B_2H_6$
0%
$AlH_3$
0%
$SiH_4$
0%
$GaH_3$

Explanation

(1)

B_{2} H_{6} :

$B_2H_6 :$ Electron deficient

(2)

A l H_{3} :

$AlH_3 :$ Electron deficient

(3)

S i H_{4} :

$SiH_4 :$ Electron precise as it has octet configuration in Si.

(4)

G a H_{3} :

$GaH_3 :$ Electron deficient

Which of the following are soluble in water?

0%
$Na_2CO_3$
0%
$BaC_2O_4$
0%
$MgCO_3$
0%
$Ca(NO_3)_2$

When a molten ionic hydride is electrolyzed

0%
hydrogen is liberated at the cathode
0%
hydrogen is liberate at the anode
0%
there is no reaction
0%
${ H }^{ - }$ ions produced migrate to the cathode

Explanation

On electrolysis molten ionic hydride liberate

H_{2}

$H_2$ gas at the anode.

At anode:

2 H^{-} \to H_{2} + 2 e^{-}

$2H^- \to H_2+2e^-$

C a H_{2}

$Ca{H_2}$ is an example of:

0%
Ionic hydride
0%
Covalent hydride
0%
Metallic hydride
0%
Polymeric hydride

Which of the following does not react with water?

0%
Li
0%
Be
0%
Na
0%
K

In lab

H_{2} O_{2}

$H _ { 2 } \mathrm { O } _ { 2 }$ is prepared by

0%
cold $H_{2} S O _ { 4 } + B a O _ { 2 }$
0%
$H C l + B a O _ { 2 }$
0%
$\mathrm { Conc } . \mathrm { H } _ { 2 } \mathrm { SO } _ { 4 } + \mathrm { Na } _ { 2 } \mathrm { O } _ { 2 }$
0%
$H _ { 2 } + O _ { 2 }$

Explanation

Hydrogen peroxide is prepared from barium peroxide by the following methods:

(a) By the action of dilute sulphuric acid. A paste of hydrated barium peroxide (

B a O 2.8 H_{2} O

$BaO2.8H_2O$ ) is prepared in ice – cold water and then added slowly to an ice-cold solution of 20%

H_{2} S O_{4}

$H_2SO_4$ .

Oxidizing properties of hydrogen peroxide are explained more by the

0%
Baeyer's formula
0%
Kingzett's formula
0%
Thenard formula
0%
Victor Meyer formula

An element reacts with hydrogen to form a compound 'A' which on treatment with water liberates hydrogen gas. The element can be:

0%
Nitrogen
0%
Chlorine
0%
Selenium
0%
Calcium

Explanation

Among all the elements, group II Calcium reacts rapidly with cold water to give hydrogen and a white precipitate of calcium hydroxide

C a + 2 H_{2} O \to C a (O H)_{2} + H_{2} ↑

$Ca+2H_ 2O\rightarrow Ca(OH)_ 2+H_ 2\uparrow$

Hence the correct answer is [D}

Hydrogen is not obtained when Zinc reacts with:

0%
Cold water
0%
dil. HCl
0%
dil. $H_2SO_4$
0%
hot 20% NaOH solution

Which of the following reaction cannot give hydrogen gas?

0%
$Zn+con.H_{2}SO_{4}$
0%
$C$ + very dil $H_{2}SO_{4}$
0%
$Mn$ + extremely dil $HNO_{3}$ ( 2 % )
0%
$Pb$ +dil $HNO_{3}$

Which of the following does not gives

H_{2} O_{2}

$H_2O_2$ ?

0%
$H_2S_2O_8+H_2O_(excess)\xrightarrow { \triangle }$
0%
$H_4P_2O_8+H_2O(excess)\rightarrow$
0%
$BaO_2+dil Acid\xrightarrow { \triangle }$
0%
$PbO_2+dil H_2SO_4\longrightarrow$

In the laboratory

H_{2} O_{2}

$H_2O_2$ is prepared by the action of :

0%
cold dilute $H_2SO_4$ on hydrated $BaO_2$
0%
dil. $HCl$ on $MnO_2$
0%
cold $H_2SO_4$ on $MnO_2$
0%
aqueous alkali on $Na_2O_2$

The boiling point of water is exceptionally high because:

0%
There is covalent bond between H and O
0%
Water molecules are linear
0%
Water molecules associate due to hydrogen bonding
0%
Water molecules are not linear.

In which of the following hydrides, the law of constant composition does not hold good:

0%
Saline hydride
0%
Metallic hydride
0%
Molecular hydride
0%
All of these

Hydrogen can be placed in VIIA ( 17th group) of periodic table because:

0%
hydrogen forms hydrides like $NaH$
0%
hydrogen has isotopes $D$ and $T$
0%
it is light
0%
hydrogen combines with halogens

The bond angle and dipole moment of water respectively are:

0%
$109.5^o, 1.84\ D$
0%
$107.5^o, 1.56\ D$
0%
$104.5^o, 1.84\ D$
0%
$102.5^o, 1.56\ D$

Explanation

The bond angle of water is

104.45

$104.45$ degrees due to the presence of two lone pairs of electrons.

The dipole moment arises because oxygen is more electronegative than hydrogen; the oxygen pulls in the shared electrons and increases the electron density around itself.

This creates an electric dipole moment vector, with the partial negative charge on the oxygen atom.

There are two

O - H

$O-H$ bonds, so the dipole moment of the molecule is the resultant vertical vector projection of the individual diagonal dipole vectors.

The dipole moment of water is

1.84 D

$1.84\ D$ .

$\mathbf{Hence\ the\ correct\ answer\ is\ option\ (C)}$ .

1561218_1726314_ans_0e808215d11d44bf875848d1feec6140.JPG

An orange coloured solution acidified with

$H_2SO_4$ and treated with a substance

$'X'$ gives a blue coloured solution of

$CrO_5$ . The substance

$'X'$ is:

0%
$H_2O$
0%
$dil. HCl$
0%
$H_2O_2$
0%
$conc. HCl$

Explanation

The orange colour solution will be

$K_2Cr_2O_7$

$K_2Cr_2O_7+H_2SO_4\rightarrow K_2SO_4 + H_2Cr_2O_7$

$H_2Cr_2O_7+4H_2O_2\rightarrow 2CrO_5+5H_2O$

_____________________________________________________

$K_2Cr_2O_7+H_2SO_4+4H_2O_2\rightarrow K_2SO_4 +2CrO_5+5H_2O$

_____________________________________________________

$\mathbf{Hence\ the\ correct\ answer\ is\ option\ (C)}$

Hydrogen peroxide was for the first time prepared by:

0%
Priestley
0%
Thenard
0%
Gay- Lussac
0%
Bernard

Water is oxidised to oxygen by:

0%
Ozone
0%
$KMnO_4$
0%
$H_2O_2$
0%
$F_2$
0%
$ClO_2$

In which of the following reactions does water act as an oxidising agent?

0%
$3F_2 +3H_2O \longrightarrow 6HF+O_3$
0%
$CaC_2 +2H_2O \longrightarrow Ca(OH)_2+C_2 H_2$
0%
$C+H_2O \longrightarrow CO+H_2$
0%
$AIN +3H_2O\longrightarrow Al(OH)_3+NH_3$

Which is not linear?

0%
$CO_2$
0%
$HCN$
0%
$C_2H_2$
0%
$H_2O$

Phosphorous is kept in:

0%
kerosene
0%
alcohol
0%
water
0%
ammonia

Which of the following is/are basic hydride (s)?

0%
$HCl$
0%
$NH_{3}$
0%
$H_{2}S$
0%
$PH_{3}$

Explanation

Hydride is a class of chemical compounds in which hydrogen is combined with another element.

$NH_3$ and

$PH_3$ are group

$15$ hydrides and have lone pairs on

$N$ and

$P$ respectively. Hence they are basic hydrides.

For pure water at an unknown temperature, the

$pH$ should always be equal to

0%
$7$
0%
$> 7$
0%
$< 7$
0%
$any\ of\ them$

When steam reacts with red hot coke to form

$CO_2$ and hydrogen:

0%
water acts as oxidising agent
0%
water acts as reducing agent
0%
carbon acts as oxidising agent
0%
there is no oxidising or reduction

Choose the correct answer for a given amount of hydrogen.

0%
Mole of $H_{2}=$ mole of $H$
0%
Equivalents of $H_{2}=$ of $H$
0%
Mole of $H_{2}=$ of $H_{2}$
0%
Mole of $H=$ of $H$

Explanation

Equivalents of

$H_2$ = Equivalents of H

mole of H = Equivalents of H

Option B and D are correct.

Which of the following choices match(es) with hydrogen gas at

$200\ atm$ and

$273\ K$ ?

0%
$Z\neq 1$
0%
Attractive forces are dominant
0%
$PV=nRT$
0%
$P(V-nb)=nRT$

Explanation

Hydrogen at high pressure behaves as real gas i.e

$\mathrm{Z \displaystyle \neq 1 }$ .

At high pressure, molecules come close to each other. So, repulsive forces dominate.

The Real Gas Equation at high pressure becomes :

$\mathrm{p(V-nb) = nRT}$

Hence, Option "A" & "D" are the correct answers.

Water is a

0%
Amphoteric in nature
0%
Aprotic solvent
0%
Protophobic solvent
0%
None of these

Explanation

Water is the most common protic solvent.
Water is an Amphiprotic solvent as it can accept protons as well as give protons.
water molecule has hydrogen atoms and, therefore, could act as an acid in a reaction. Since water has the potential to act both as an acid and as a base, $\text{water is amphoteric}$

thus, A is the correct answer.

Hydrogen by donating one electron forms

$H^+$ . In this property, it resembles with

0%
Transitional elements
0%
Alkaline earth metals
0%
Alkali metals
0%
Halogens

Explanation

Alkali metals have one electron in outermost orbital. They can easily remove an electron to attain noble gas configuration. Hence properties of

$H^{+}$ resemble with alkali metal.

Which of the followings explanation is best for

0%
The ionization energy of hydrogen is too high for group of alkali metals but too low of halogens group
0%
Hydrogen can form compounds with all other elements
0%
Hydrogen is much lighter than the alkali metals or the halogens
0%
None of these

The surface tension of which of the following liquid is maximum

0%
$H_{2}O$
0%
$C_{6}H_{6}$
0%
$CH_{3}OH$
0%
$C_{2}H_{6}OH$

The oxidation number of hydrogen in

${MH}_{2}$ is

0%
$+1$
0%
$-1$
0%
$+2$
0%
$-2$

Explanation

In all alkali and alkaline earth metal hydride hydrogen always shows

$-1$ oxidation state

$C+{H}_{2}O\rightarrow CO+{H}_{2},\ {H}_{2}O$ acts as

0%
Oxidising agent
0%
Rducing agent
0%
(A) and (B) both
0%
None of these

Explanation

$C+{H}_{2}O\rightarrow CO+{H}_{2}$

In the above reaction,

${H}_{2}O$ acts as oxidising agent since it oxidises

$C$ to

$CO$ .

Heavy water freezes at

0%
$0^\circ C$
0%
$3.8^\circ C$
0%
$38^\circ C$
0%
$-0.38^\circ C$

Explanation

$\text{Freezing point of heavy water is }3.8^oC.$ Heavy water is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium, rather than the common hydrogen-

1

isotope that makes up most of the hydrogen in regular water.

Which of the following reaction produces hydrogen?

0%
$Mg+H_{2}O$
0%
$BaO_{2}+HCl$
0%
$H_{2}S_{4}O_{8}+H_{2}O$
0%
$Na_{2}O_{2}+2HCl$

Explanation

Alkali and alkaline earth metals react with water to produce hydrogen gas and metal hydroxide. This is due to their high electropositive character.

$Mg+H_{2}O \rightarrow Mg(OH)_2 + H_2$

Hence correct ans is option (A).

Hydrogen is

0%
electropositive
0%
electronegative
0%
both electropositive as well as electronegative
0%
neither electropositive nor electronegative

Explanation

Hydrogen is both electropositive as well as electronegative.

Like alkali metals,

$H$ has tendency to lose its one valency electron to form unipositive hydrogen ion

$H^+$ .

Hence, hydrogen is electropositive in nature.

Like halogens, hydrogen has tendency to gain one electron and form uninegative ion

$H^−$ .

Hence, hydrogen is electronegative in nature.

What happens when electric current is passed through an ionic hydride in the molten state?

0%
Hydrogen is liberated at the anode
0%
Hydrogen is liberated at the cathode
0%
No reaction takes place
0%
Hydride ion migrates towards cathode

Explanation

$M^+H^- \rightarrow M^+ + H^-$ where M is a metal.

At anode:

$2H^- \rightarrow H_2 + 2e^-$

In all its properties, hydrogen resembles

0%
alkali metals only
0%
halogens only
0%
both alkali metals and halogens
0%
neither alkali metals nor halogens

Hydrogen readily combines with non-metals and thus it shows its

0%
electronegativity character
0%
electropositive character
0%
both (A) and (B)
0%
none of these

Explanation

$H_2 + Cl_2 \rightarrow 2HCl$

Here, hydrogen combines with non metal chlorine and shows it's electropositive character.

Hydrogen molecule differs from chlorine molecule in which of the following respect?

0%
Hydrogen molecule is non-polar but chlorine molecule is polar
0%
Hydrogen molecule is polar while chlorine molecule is non-polar
0%
Hydrogen molecule can from intermoelcular hydrogen bonds but chlorine molecule can not
0%
Hydrogen molecule cannot participate in coordination bond formation but chlorine molecule can

lonization energy of hydrogen is

0%
Equal to that of chlorine
0%
Lesser than that of chlorine
0%
Slightly higher than that of chlorine
0%
Much higher than that of chlorine

Which of the following explanation is best for not placing hydrogen with alkali metals or halogen?

0%
The ionization energy of hydrogen is too high for group of alkali metals but too low for halogen group
0%
Hydrogen can form compounds
0%
Hydrogen is a much lighter element than the alkali metals or halogens
0%
Hydrogen atom does not contain any neutron

CBSE Questions for Class 11 Medical Chemistry Hydrogen Quiz 9 - MCQExams.com

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Practice Class 11 Medical Chemistry Quiz Questions and Answers

CBSE Questions for Class 11 Medical Chemistry Hydrogen Quiz 9 - MCQExams.com

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Practice Class 11 Medical Chemistry Quiz Questions and Answers

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