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

Direction: Following chemical species were reported for water sample from a well:

 
Specials Concentration (milli equivalent/L)
Choride (Cl–) 15
Sulphate (SO42–) 15
Carbonate (CO32–) 05
Bicarbonate (HCO3–) 30
Cacium (Ca2+) 12
Magnesium (Mg2+) 18
pH 8.5

Total hardness in mg/L as CaCO3 is

  1. 1500

  2. 2000

  3. 3000

  4. 5000
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 $\text{Total hardness as} CaCO_3 \\ \hspace{1cm} = (12 \times 50 + 18 \times 50) = 1500\\ \text{Note:- Milliequivalent/L}\\ \text{Equivalent weight of} CaCO_3 = 50$

Multiple choice

Direction: Following chemical species were reported for water sample from a well:

 
Specials Concentration (milli equivalent/L)
Choride (Cl–) 15
Sulphate (SO42–) 15
Carbonate (CO32–) 05
Bicarbonate (HCO3–) 30
Cacium (Ca2+) 12
Magnesium (Mg2+) 18
pH 8.5

Alkalinity present in the water in mg/L as CaCO3 is

  1. 250

  2. 1500

  3. 1750

  4. 5000
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

 $\text{Alkalinity = Due to bicarbonate and carbonate only}\\ \hspace{1.9cm} = (30 + 5) \times 50 = 1750 mg/L \hspace{0.2cm} \text{as} \hspace{0.2cm}CaCO_3$

Multiple choice

Which of the following is the name of NaClO2?

  1. Sodium chlorate

  2. Sodium chloride

  3. Sodium chlorite

  4. Sodium per chlorate
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Suffix ‘ite’ is used, if number of oxygen atoms is less. Suffix ‘ate’ is used, if number of oxygen atoms is more. Sodium chlorite has formula NaClO2, while formula of sodium chlorate is NaClO3.

Multiple choice

In which of the following is hard water produced?

  1. Saturation of water with calcium carbonate

  2. Saturation of water with magnesium carbonate

  3. Saturation of water with calcium sulphate

  4. Addition of sodium sulphate to water

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

Ca and Mg soluble sulphates and chlorides cause permanent hardness. 

Multiple choice

Which of the following combinations of salts and their uses is incorrect?

  1. Silver nitrate - To develop photographic films

  2. Calcium carbonate - In marbles for flooring

  3. Sodium bicarbonate - To make chalk

  4. Ammonium nitrate - In explosives

  5. Sodium carbonate - In detergents
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Calcium carbonate is used to make chalk. Sodium bicarbonate is used in bakery and medicines.