Chemistry · Science General

Common Chemical Compounds and Reactions

1,197 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

Which of the following compounds is one of the constituents of gunpowder?

  1. Potassium hydroxide

  2. Potassium iodide

  3. Potassium nitrate

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

Potassium hydroxide is an inorganic compound with the formula KOH. Its common name is caustic potash. It has many industrial and niche applications. Most applications exploit its reactivity towards acids and its corrosive nature. Potassium iodide is an inorganic compound with the chemical formula KI. This white salt is the most commercially significant iodide compound. It is used to loosen and break up mucus in the airways.  Potassium nitrate is a natural solid source of nitrogen. Major uses of potassium nitrate are in fertilisers, rocket propellants and fireworks. It is one of the constituents of gunpowder. Potassium oxide is an important compound used in fertilisers, ceramics, glass and optics.   

Multiple choice

Which of the following salts plays a crucial role in fertiliser industry?

  1. Calcium chloride

  2. Potassium carbonate

  3. Potassium chlorate

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

Calcium chloride behaves as an ionic halide and is solid at room temperature. Common applications include brine for refrigeration plants, ice and dust control on roads and desiccation. Potassium carbonate is a white salt, which forms a strongly alkaline solution. It is used in the production of soap and glass. Potassium chlorate is a white crystalline substance. It is the most common chlorate in industrial use. It is used as an oxidising agent as a disinfectant in safety matches, explosives and fireworks. Potassium chloride (KCl) is a metal halide salt composed of potassium and chlorine. In its pure state, it is odourless and has a white or colourless vitreous crystal appearance. The majority of potassium chloride produced is used for making fertilisers as the growth of many plants is limited by their potassium intake.

Multiple choice

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

  1. Sodium carbonate - In detergents

  2. Silver nitrate - To develop photographic films

  3. Calcium carbonate - In marbles for flooring

  4. Sodium bicarbonate - To make chalk

  5. Ammonium nitrate - In explosives
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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

Multiple choice

The formula of quicklime is

  1. Ca(OH)2

  2. CaCl2

  3. CaO

  4. CaSO4
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The formula of quicklime is CaO. It is also called calcium oxide.

Multiple choice

The chemical name of baking soda is

  1. sodium carbonate

  2. sodium hydrogen carbonate

  3. calcium carbonate

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

The chemical name of baking soda is sodium hydrogen carbonate.

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

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