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

Which of these is not an example of neutralization?

  1. taking antacid pills for indigestion

  2. adding alkalis to lakes

  3. using toothpaste

  4. adding lime to coca-cola
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Neutralization is a reaction between an acid and an alkali. Adding lime (an alkali) to Coca-Cola (an acidic drink) is a neutralization reaction, so the premise of the question is slightly confusing, but it is the only option that fits the chemical definition of neutralization.

Multiple choice

Which of these is an alkali?

  1. toothpaste

  2. hydrochloric acid

  3. sugar

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

Toothpaste is slightly alkaline to help neutralize the acids produced by bacteria in the mouth.

Multiple choice

Baking soda is a mixture of:

  1. Sodium carbonate and acetic acid

  2. Sodium carbonate and tartaric acid

  3. Sodium hydrogen carbonate and tartaric acid

  4. Sodium hydrogen carbonate and acetic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Baking powder is a mixture of baking soda (sodium hydrogen carbonate) and a mild edible acid like tartaric acid. When mixed with water, the acid reacts with the base to release carbon dioxide.

Multiple choice

calcium carbonate

  1. Ca3CO

  2. CaCO3

  3. Ca2CO3

  4. Ca3Co3
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Calcium (Ca) has a 2+ charge and carbonate (CO3) has a 2- charge. They combine in a 1:1 ratio to form CaCO3.

Multiple choice

ammonium carbonate

  1. Am3CO

  2. NH4CO3

  3. (NH4)2CO3

  4. Am3CO3
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ammonium (NH4) has a 1+ charge and carbonate (CO3) has a 2- charge. Two ammonium ions are needed to balance one carbonate ion, resulting in (NH4)2CO3.

Multiple choice

The chemical formula for table salt is

  1. NaCl

  2. H2O

  3. C6H12O6

  4. CH4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Table salt is chemically known as sodium chloride, represented by the formula NaCl. H2O is water, C6H12O6 is glucose, and CH4 is methane.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Gypsum, $CaSO _4.2H _2O$, on heating to about $120^0C$ forms a compound which has the chemical composition represented by 

  1. $CaSO _4.1/2H _2O$
  2. $CaSO _4$
  3. $CaSO _4.H _2O$
  4. $2CaSO _4.3H _2O$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Heating gypsum (CaSO4.2H2O) to 120 degrees Celsius drives off 1.5 molecules of water, resulting in Plaster of Paris, which is calcium sulfate hemihydrate (CaSO4.1/2H2O).

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

In aqueous solution, the most stable sulphate is :

  1. $Be{SO} _{4}$
  2. $Mg{SO} _{4}$
  3. $Ca{SO} _{4}$
  4. $Ba{SO} _{4}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Solubility of alkaline earth metal sulfates decreases down the group. Magnesium sulfate is highly soluble in water, making it the most stable in aqueous solution compared to the others which are less soluble or insoluble.

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

Which of the following is INCORRECT statement:

  1. Above 373 k,$Na _2CO _3,10H _2O$ converted into anhydrous form
  2. Hemihydrate of $CaSO _4$ is known as Gypsum
  3. $NaHCO _3$ act as weak antiseptic for skin infections

  4. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Gypsum is a hydrated calcium sulphate (CaSO4. 2H2O). Plaster of Paris is calcium sulphate hemihydrate. 

Multiple choice some important compounds of magnesium and calcium the s-block elements chemistry

The tribasic form of calcium phosphate is ________ in water.

  1. soluble

  2. insoluble

  3. sparingly soluble

  4. soluble only at high temperature
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Tricalcium phosphate (TCP) is a calcium salt of phosphoric acid with the chemical formula $Ca _3(PO _4) _2$. It is also known as tribasic calcium phosphate and bone phosphate of lime (BPL). It is a white solid, with very low solubility.