CBSE Questions for Class 11 Medical Chemistry Hydrogen Quiz 7 - MCQExams.com

Steam reforming is a method for producing hydrogen, carbon monoxide, or other useful products from hydrocarbon fuels such as natural gas. This is achieved in a processing device called a reformer which reacts steam at high temperature with the fossil fuel.

Steam reforming of natural gas - sometimes referred to as steam methane reforming (SMR) - is the most common method of producing commercial bulk hydrogen. Hydrogen is used in the industrial synthesis of ammonia and other chemicals. At high temperatures (700 – 1100 °C) and in the presence of a metal-based catalyst (nickel), steam reacts with methane to yield carbon monoxide and hydrogen.

$$C{ H }_{ 4 }+{ H }_{ 2 }O\leftrightharpoons CO+3{ H }_{ 2 }$$

The Wurtz reaction, named after Charles-Adolphe Wurtz, is a coupling reaction in organic chemistry, organometallic chemistry and recently inorganic main group polymers, whereby two alkyl halides are reacted with sodium to form a new alkane:

$$2R–X+2{ Na }^{ + }\longrightarrow R–R+2{ Na }^{ + }+{ X }^{ - }$$

In chemistry, an arsenite is a chemical compound containing an arsenic oxoanion where arsenic has oxidation state +3. Sodium arsenite is used in the water gas shift reaction to remove carbon dioxide.

The electrolyte is dilute sulphuric acid (= acidified water) which, during electrolysis is split into hydrogen and oxygen gases.

Electrolysis (of acidified water) is a way of splitting up (decomposition) of the compound (water) using electrical energy. The electrical energy comes from a d.c. (direct current) battery or power pack supply. A conducting liquid, containing ions, called the electrolyte (dilute sulphuric acid), must contain the compound (water) that is being broken down. The electricity must flow through electrodes dipped into the electrolyte to complete the electrical circuit with the battery. Electrolysis can only happen when the circuit is complete, and an electrical current (electricity) is flowing, then the products of electrolysing dil. sulfuric acid are released on the electrode surfaces where they can be collected. Electrolysis always involves a flow of electrons in the external wires and electrodes and a flow of ions in the electrolyte and there is always a reduction at the negative cathode electrode (which attracts positive ions, cations) and an oxidation at the positive anode electrode (which attracts negative ions, anions) and it is the ions which are discharged to give the products.

Sodium hydride is an ionic compound which decomposes below its melting point, so it would be extremely difficult to obtain molten sodium hydride in the first place.

However, if you were able to somehow melt some sodium hydride, its electrolysis would produce liquid sodium metal at the cathode and hydrogen gas at the anode;-

Cathode reaction:

$$2{ Na }^{ + }+2{ e }^{ - }\longrightarrow 2{ Na }_{ (l) }$$

Anode reaction:

$$2H\longrightarrow { H }_{ 2(g) }+2{ e }^{ - }$$

The overall reaction is:

$$2Na{ H }_{ (l) }\longrightarrow 2{ Na }_{ (l) }+{ H }_{ 2(g) }$$

Hint: The water gas shift reaction is the reaction of carbon monoxide and water vapor to form carbon dioxide and hydrogen.

Explanation:

• The production of dihydrogen is increased by reacting carbon monoxide of synthesis gas mixture with the steam. 

• The reaction is catalyzed by iron chromate.

• Reaction is: 

Hence, the correct answer is option $$(C).$$

Zinc will react with Sodium Hydroxide to from Sodium Zincate. In this reaction Zinc will not displace sodium from sodium hydroxide, but will displace Hydrogen as shown below:

$$2NaOH+Zn\longrightarrow { Na }_{ 2 }Zn{ O }_{ 2 }+{ H }_{ 2 }$$

This reaction is accompanied by evolution of Hydrogen gas.

 Pure hydrogen gas can be prepared by the electrolysis of warm solution of barium hydroxide using platinum or nickel electrodes. As water does not conduct electricity very well, so it is usual to electrolyse aqueous solution of barium hydroxide. The gases produced in the anode and cathode compartment must be kept separate. Following reactions occur at anode and cathode.