Chemistry

Chemical Reactions and Processes

626 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 chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Compound which on heating with sodium hydroxide produces a gas which forms dense white fumes with hydrogen chloride?

  1. Chlorine

  2. Lead carbonate

  3. Ammonium sulphate

  4. Iron [II] sulphate
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ammonium sulphate is the compound formed which on heating with sodium hydroxide produces a gas which forms dense white fumes with hydrogen chloride.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

When $Na$ reacts with liquid $NH _3$ the following substance is formed: 

  1. $[Na(NH _3) _x]^- $
  2. $ [e(NH _3 ) _y]^-$
  3. $NaNH _2$
  4. $Na _xNH _{3y}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sodium (Na) dissolves in liquid ammonia ($NH _3$) solution to form a blue colored solution characteristic of a solvated electron in liquid ammonia which is conducting in nature due to presence of solvated electrons.

Reaction is  $ Na + (x+y)NH _3\rightarrow Na(NH _3) _x + (e(NH _3) _y)^-$
So B is correct answer. 

Multiple choice

Oxygen acts as final hydrogen acceptor

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In aerobic respiration, oxygen is the final electron acceptor in the electron transport chain, where it combines with electrons and protons to form water.

Multiple choice

Are Chemical Changes reversible?

  1. Not Easily

  2. No

  3. Yes

  4. Easily
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chemical changes involve the formation of new substances by breaking and forming chemical bonds. These processes are generally not easily reversible, unlike physical changes.

Multiple choice

When an acid and an alkali react together:

  1. a salt and water are both produced

  2. only a salt is produced.

  3. a metal is formed

  4. a gas is given off
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The reaction between an acid and an alkali (a base) is a neutralization reaction, which always produces a salt and water.

Multiple choice

When an acid reacts with a metal carbonate, the products are:

  1. the metal and carbon dioxide

  2. a salt and water

  3. carbon dioxide, water and a salt.

  4. the metal, a salt and water.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The general word equation for the reaction between an acid and a metal carbonate is: acid + metal carbonate -> salt + water + carbon dioxide.

Multiple choice

If an acid reacts with a metal, the products are:

  1. a salt and water

  2. a salt and hydrogen gas

  3. only hydrogen gas

  4. a salt, water and carbon dioxide
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The general word equation for the reaction between a metal and an acid is: metal + acid -> salt + hydrogen gas.

Multiple choice

When some acid is put onto a piece of metal:

  1. there is always a reaction which burns a hole in the metal.

  2. there is never a reaction

  3. some metals will react and produce bubbles of gas.

  4. there is always a reaction, which produces a powder
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Not all metals react with acids (e.g., copper or gold do not react with dilute acids). For those that do, the reaction typically produces a salt and hydrogen gas, which appears as bubbles.