Chemistry

Chemical Reactions and Processes

571 Questions

Chemical reactions and processes questions cover the transformation of substances through electrolysis, thermal decomposition, and catalysis. Key areas include identifying gas evolution, balancing chemical equations, and understanding industrial chemical applications. This general chemistry topic is a staple in the science sections of multiple competitive examinations.

Thermal decompositionElectrolysis processGas evolution reactionsHeterogeneous catalystsFuel cell components

Chemical Reactions and Processes Questions

Multiple choice

By which of the following reactions can gold sol be prepared?

  1. Hydrolysis of gold(III) chloride

  2. Oxidation of gold by aqua regia

  3. By peptization

  4. Reduction of gold (III) chloride formalin solution

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct because gold chloride reacts with formaldehyde and water to give gold sol and formic acid.

Multiple choice

Which gas liberates when water reacts with metal?

  1. Hydrogen

  2. Nitrogen

  3. Oxygen

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When reactive metals (like sodium or potassium) react with water, they displace hydrogen, resulting in the liberation of hydrogen gas.

Multiple choice

Carbon reacts with metals to form____.

  1. carbonate

  2. chloride

  3. bi carbonate

  4. carbide
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Carbon reacts with certain metals at high temperatures to form binary compounds known as carbides. Examples include calcium carbide (CaC2) and silicon carbide (SiC).

Multiple choice

Which one of the following is a property of a solution of dry hydrogen chloride in dry methylbenzene?

  1. It produces useful hydrochloric acid as a byproduct.

  2. It has a pH approximately reaching to 7.

  3. It is a non-conductor of electricity.

  4. It reacts with magnesium to give hydrogen.

  5. It shows acidic properties.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

HCl dissociates into ions in water but remains as molecules in organic solvents. All properties are related to this only eg it conducts electricity in water but not in methylbenzene.

Multiple choice

Amphoteric oxide can react with

  1. acids
  2. alkalies

Choose the correct option.

  1. Reacts with acids only

  2. Reacts with alkalies only

  3. No reaction at all

  4. Reacts with acids as well as alkalies

  5. Do not react with acids and bases
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

These are oxides of metals which are slightly covalent in nature. So, they show both acidic and basic character, and react with both to form salt and water.