Chemistry · Science General

Common Chemical Compounds and Reactions

1,204 Questions

Common chemical compounds and reactions questions test your knowledge of everyday chemicals, their formulas, and their interactions. Topics include properties of acids and bases, hard water chemistry, and compounds like baking soda and plaster of paris. This section is essential for general science preparation.

Acids and basesPlaster of parisHard water chemistryCommon chemical formulasEveryday chemical reactions

Common Chemical Compounds and Reactions Questions

Multiple choice

Hard water does not lather well with soap because

  1. it contains carbonates of calcium and magnesium

  2. it is highly coloured

  3. it contains suspended impurities

  4. it contains sodium chloride
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hard water contains calcium and magnesium ions that react with soap to form insoluble precipitates (scum) instead of lather.

Multiple choice

Synthetic detergents are

  1. sodium salts of fatty acids

  2. a mixture of sodium carbonate and sodium chloride

  3. calcium salts of hydrochloric acid

  4. a mixture of sodium salts of aromatic and aliphatic sulphonic acids
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Synthetic detergents are typically sodium salts of long-chain alkyl benzene sulphonic acids or similar compounds, which do not form scum with hard water.

Multiple choice

Laundry soap is

  1. a mixture of sodium salt of higher fatty acids of natural origin

  2. sodium carbonate

  3. sodium sulphate

  4. a mixture of sodium salts of synthetic sulphonic acids
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Laundry soap is chemically the sodium or potassium salt of long-chain fatty acids, typically produced via saponification of fats and oils.

Multiple choice

What is washing soda?

  1. Sodium chloride

  2. Hydrated sodium carbonate

  3. Sodium bicarbonate

  4. Calcium carbonate
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Washing soda is the common name for sodium carbonate decahydrate (Na2CO3.10H2O). Sodium bicarbonate is baking soda, and sodium chloride is common salt.

Multiple choice

Toilet soap is a mixture of:

  1. Na salt of long-chain fatty acids

  2. heavy metals like Al with fatty acids

  3. KOH with fatty acids

  4. K salts of fatty acids
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A toilet soap is a cleansing agent made from the potassium salts of vegetable or animal fats. It is a mild soap, often coloured and scented, used for washing oneself .

Multiple choice

Which of the following is least soluble in water?

  1. BaCrO4

  2. MgCrO4

  3. SrCrO4 .

  4. CaCrO4

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 If abigger anion is attached to the alkali and alkaline earth metal groups , solubility decrease down the group . because solubilty depends on the the lattice energy  and hydration energy and in this case lattice energy > hydration energy . U lattice energy  = ( Z+ Z-) / (r + + r-) and  U hydration energy  = (Z+/r+) +( Z-/r- ) . Lattice energy increases down the group at faster rate than that of hydration energy . Hence, this option is correct.

Multiple choice

For which of the purposes is sulfuric acid not used?

  1. As an electrolyte

  2. Production of fertilizers

  3. As a dehydrating agent

  4. For designing glass and metal
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The nitric acid is used to make patterns and designs on glass and metal, including jewelry.

Multiple choice

What is the chemical name of baking soda?

  1. Sodium bicarbonate

  2. Sodium nitrate

  3. Sodium carbonate

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

The chemical name for baking soda is sodium bicarbonate, with the chemical formula NaHCO3.

Multiple choice

Synthetic detergent is

  1. sodium salt of fatty acids

  2. a mixture of sodium carbonate and sodium chloride

  3. calcium salt of hydrochloric acid

  4. a mixture of sodium salt of aromatic and aliphatic sulphonic acid
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice

Absorbency of talcum powder can be increased by adding

  1. magnesium carbonate

  2. boric acid

  3. magnesium and zinc stearates

  4. titanium dioxide, zinc oxide and magnesium dioxide

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

It is about five times more powerful than talc in absorbing water. Hence it is often used to enhance absorbency and lightness of powders.

Multiple choice

Which of the following is not used as a preservative?

  1. Sodium benzoate

  2. Vinegar

  3. Potassium metabisulphite

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

It is an edible colour and is not used as a preservative. Food colours are used in, ice creams, dairy products, sweet meat, soft drinks, confectionery, etc.. These colours are also used in oral medicines like capsules, tablets, syrups and liquids, to improve their appearance.

Multiple choice

Which of the following soaps contain glycerol?

  1. Floating Soaps

  2. Transparent Soaps

  3. Medicated Soaps

  4. Shaving Soaps

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Transparent Soaps contain glycerol or alcohol. These are obtained by dissolving soap in alcohol and evaporating the solvent alcohol.

Multiple choice

Sodium carbonate does not make water hard because

  1. it is insoluble in water

  2. sodium salts of higher fatty acids are water soluble

  3. sodium salts of higher fatty acids are colourless

  4. it is a crystalline solid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sodium carbonate (washing soda) does not cause hardness because sodium salts of higher fatty acids are water-soluble, unlike calcium and magnesium salts which form insoluble precipitates (soap scum). The other options are incorrect: sodium carbonate is soluble in water, color is unrelated to water hardness, and being crystalline has no connection to water softening.

Multiple choice

Which is a compound?

  1. Vinegar

  2. Salt

  3. Milk

  4. Tin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A compound is a substance formed when two or more chemical elements are chemically bonded together. Salt (sodium chloride) is a compound, whereas vinegar is a mixture, milk is a colloid/mixture, and tin is an element.