Tag: properties of acids and bases

Questions Related to properties of acids and bases

Which of the following is used for dissolution of gold ? 

  1. Hydrochloric acid

  2. Sulphuric acid

  3. Nitric acid

  4. Aqua regia


Correct Option: D
Explanation:

Gold,palladium,gallium are all noble metals which are dissolved in aqua regia. It is also known as royal water which is a mixture of hydrochloric acid and nitric acid in the ratio of 3:1 respectively.

Which of the following acid is used in fire extinguishers?

  1. Hydrochloric acid

  2. Sulphuric acid

  3. Nitric acid

  4. Oxalic acid


Correct Option: B
Explanation:

Sulphuric acid is non flammable so soda acid is most common fire extinguisher. Carbon dioxide is liberated by the action of sulphuric acid on baking soda or sodium bicarbonate. This increases the percentage of carbon dioxide in air. Due to this the supply of air is cut off and fire is extinguished.

Which of  the following acids is called the king of the acids?

  1. Acetic acid

  2. Phosphoric acid

  3. Oxalic acid

  4. Sulphuric acid


Correct Option: D
Explanation:

Sulphuric acid is diprotic acid and shows different properties depending upon its concentration. It is a strong acid and in concentrated form it has strong dehydrating and oxidising properties. It has large number of applications. In almost all industrial processes sulphuric acid is used,in production of lead acid batteries,production of fertilizers,in chemistry labs,petroleum refining and production of paper. So it is called as the king of all acids.

The acid generally stored in batteries is :

  1. sulphuric acid

  2. nitric acid

  3. hydrochloric acid

  4. acetic acid


Correct Option: A
Explanation:

Sulphuric acid develops voltage from the chemical reaction produced when two unlike materials such as the positive and negative plates are immersed in the electrolyte a solution of sulphuric acid and water. In typical lead-acid battery the voltage is approx. 2 volts per cell for a total of 12 volts.

Soda-acid fire extinguisher extinguishes the fire by :

  1. cutting the supply of air

  2. removing the combustible substance

  3. raising the ignition temperature

  4. none of these


Correct Option: A
Explanation:
The principle of working of fire extinguisher is based on either of the following three conditions: 
• cooling the combustible material below its ignition temperature, or 
• cutting off the supply of air, or 
• cooling the combustible material and at the same time cutting the supply of air. 

When marble chips are treated with $HCl $, which of the following gas is liberated?

  1. CO$ _2$

  2. O$ _2$

  3. CO

  4. NO$ _2$


Correct Option: A
Explanation:

Reaction:

$\underbrace{CaCO _3} _{(Marble\quad chips)} +2HCl\longrightarrow CaCl _2+CO _2(g) +H _2O(l)$
So, $CO _2$ gas is liberated.

$Ca(HCO _{3}) _{2} + 2HCl \rightarrow $

  1. $CaCl _{2} + 2H _{2}O + 2CO _{2}$

  2. $2CaCl _{2} + 2H _{2}O + 2CO _{2}$

  3. $CaCl _{2} + 4H _{2}O + 2CO _{2}$

  4. $CaCl _{2} + 2H _{2}O + 4CO _{2}$


Correct Option: A
Explanation:

$Ca(HCO _{3}) _{2} + 2HCl \rightarrow CaCl _{2} + 2H _{2}O + 2CO _{2}$ 

Metal carbonates react with  acids to give salt, carbon dioxide and water.

Acids react with carbonate and bicarbonates to liberate $CO _{2}$.

  1. True

  2. False


Correct Option: A
Explanation:

The metal ion displaces the proton $(H^+)$ from the acid and a salt is formed along with carbonic acid $(H _2CO _3)$

However, $(H _2CO _3)$ is unstable in atmospheric conditions.
$MgCO _3+2HCl\longrightarrow MgCl _2+H _2CO _3$ (Equation $01$)
$H _2CO _3\longrightarrow H _2O+CO _2$ (Equation $02$)
By adding $01$ and $02$
$MgCl _2+2HCl\longrightarrow MgCl _2+H _2O+CO _2$
Similarly,
$Na _2CO _3+H _2SO _4\longrightarrow Na _2SO _4+H _2CO _3$
here, $H _2CO _3$ is split into $H _2O+CO _2$
$ZnCO _3+2HNO _3\longrightarrow Zn(NO _3) _2+H _2O+CO _2$

Metal carbonates react with _______ to give salt, carbon dioxide and water.

  1. acids

  2. bases

  3. alkalis

  4. non-metals


Correct Option: A
Explanation:

Metal carbonates react with acids to give salt, carbon dioxide and water.
$NaHCO _{3} + 2HCl (dil) \rightarrow NaCl + H _{2}O + CO _{2(g)}$.

Choose the correct option to complete the reaction.
$CaCO _{3}(s) + 2HCl(aq) \rightarrow $

  1. $2CaCl _{2}(aq) + H _{2}O(l) + CO _{2}(g)$

  2. $CaCl _{2}(aq) + 3H _{2}O(l) + CO _{2}(g)$

  3. $2CaCl _{2}(aq) + 4H _{2}O(l) + CO _{2}(g)$

  4. $CaCl _{2}(aq) + H _{2}O(l) + CO _{2}(g)$


Correct Option: D
Explanation:

$CaCO _{3}(s) + 2HCl(aq) \rightarrow CaCl _{2}(aq) + H _{2}O(l) + CO _{2}(g)$ 

All metal carbonates and hydrogen carbonates react with acids to gives corresponding salt, carbon dioxide and water.