Download App

CHEMISTRY [2 Mark Question Answer]

Acids, Bases and Salts · ICSE STD 7 (ICSE - English Medium). 9 questions.

Questions

[2 Mark Question Answer]

🎯

Test yourself on this topic

9 questions · timed · auto-graded

Question 12 Marks
Ammonium hydroxide is a weak base.
Answer
Ammonium hydroxide is a weak base because it undergoes partial dissociation in aqueous solution and produce a low concentration of hydroxyl ions (OH–) in solution.
View full question & answer→
Question 22 Marks
One molecule of acetic acid has four hydrogen atoms, yet it is called a monobasic acid.
Answer
In acetic acid $(CH_3COOH),$ four hydrogen atoms are present but only one hydrogen is capable of ionizing. Hence, it is called a monobasic acid. Its dissociation in aqueous solution is $CH_3COOH \rightarrow CH_3COO + H^+$
View full question & answer→
Question 32 Marks
Define the terms : pH scale
Answer
pH scale is a scale (0-14) which gives the strength of an acid and a base as the measure of hydrogen ion concentration in the solution. Neutral solutions have pH equal to 7. Acidic solutions have pH less than 7. Basic solutions have pH more than 7.
View full question & answer→
Question 42 Marks
Define the terms : Neutralization
Answer
A neutralization reaction is a reaction between an acid and a base to form salt (which is neutral) and water i.e.
acid + base → salt + water
Example:
$\underset{\text {sodium hydroxide (base)}}{NaOH} + \underset{\text {hydrochloric acid (acid)}}{HCl} \longrightarrow \underset{\text {sodium chloride (neutral salt)}}{NaCl} + \underset{\text {water}}{H_2O}$
View full question & answer→
Question 52 Marks
Define the terms : Alkali
Answer
An alkali is a base soluble in water.
Example :
sodium hydroxide (NaOH), potassium hydroxide, etc.
View full question & answer→
Question 62 Marks
Define the terms : Acid
Answer
An acid is a compound which, when dissolved in water, yields hydronium ions $(H_3O^+)$
Example : Hydrochloric acid
Image
View full question & answer→
Question 72 Marks
Name the products formed when an acid reacts with a base.
Answer
When an acid reacts with a base, it forms salt (which is neutral) and water. This reaction is called neutralization reaction.
acid + base $\rightarrow$ salt + water
View full question & answer→
Question 82 Marks
What happens when an acid reacts with sodium carbonate ? Write the balanced chemical equation of the reaction involved.
Answer
When an acid reacts with sodium carbonate, carbon dioxide gas is liberated with brisk effervescence and sodium salt and water are formed.
$\underset{\text {sodium carbonate}}{Na_2CO_3} + \underset{\text {dil. sulphuric acid}}{H_2SO_4} \longrightarrow \underset{\text {sodium sulphate}}{Na_2SO_4} + \underset{\text {water}}{H_2O} +\underset {\text {carbon dioxide}}{CO_2}$
View full question & answer→
Question 92 Marks
Choose strong and weak acids as well as strong and weak bases from the following :
$H_2CO_3, HNO_3, CH_3COOH, CU(OH)_2, NH_4OH, KOH, Ca(OH)_2, HCl$
Answer
Strong acids $– HCl, HNO_3$ Weak acids $– H2CO_3, CH_3COOH$ Strong bases $– KOH, Ca(OH)_2$​​​​​​​ Weak bases $– NH_4OH, Cu(OH)_2$​​​​​​​
View full question & answer→
Generate Paper FreeAll Acids, Bases and Salts topics
[2 Mark Question Answer] - CHEMISTRY STD 7 Questions - Vidyadip