Maharashtra Board Class 8 Introduction to Acid and Base , Textbook Exercises This page includes Fill in the Blanks, Questions and Answers, as well as Additional Questions and Answers for the chapter.
Write chemical names from given formulae.
H2SO4, Ca(OH)2, Hcl, Naoh, KOH,NH4OH
- H2SO4 – Sulfuric acid
- Ca(OH)2 – Calcium hydroxide
- Hcl – Hydrochloric acid
- Naoh – Sodium hydroxide
- KOH – Potassium hydroxide
- NH4OH – Ammonium hydroxide
Give answers.
 Which acid is used for getting chloride salt?
Hydrochloric acid (hcl) is used for obtaining chloride salts.
By squizzing lemon on a piece of rock the gas liberated turned lime water milky. Which compound is present in the rock?
The gas liberated when lemon juice is squeezed on a piece of rock and turns lime water milky is carbon dioxide (CO2). The presence of carbonates in the rock is indicated by this reaction.
The label on the bottle of chemical is spoiled. How will you find whether the chemical is acidic or not?
To determine whether the chemical is acidic or not, you can use a ph indicator paper or solution. Dip the ph paper into the chemical or place a drop of the solution on the paper. The color change of the ph paper will indicate the acidity or alkalinity of the chemical. If it turns red, the substance is acidic; if it turns blue or green, it may be alkaline.
Answer the following questions.
 Explain the difference between acid and base.
| Characteristic | Acid | Base |
| Taste | Sour | Bitter |
| Touch | Corrosive (may burn) | Slippery |
| Ph Range | 0 to 7 | 7 to 14 |
| Litmus Test | Turns blue litmus paper red | Turns red litmus paper blue |
| Chemical Formula | Contains hydrogen ions (H+) | Contains hydroxide ions (OH-) |
| Reaction with Metals | Reacts to produce hydrogen gas | Reacts to produce hydroxide ions |
| Examples | Hydrochloric acid (hcl), Sulphuric acid (H2SO4) | Sodium hydroxide (naoh), Potassium hydroxide (KOH) |
Why indicator does not get affected by salt?
Indicators do not get affected by salt because salts are typically formed by the neutralization reaction between an acid and a base. In this reaction, the hydrogen ions (H+) from the acid combine with the hydroxide ions (OH-) from the base to form water, leaving behind a salt. Since indicators are sensitive to the concentration of hydrogen ions or hydroxide ions, the neutralization process results in a balanced ph, and therefore, the indicator does not show a significant color change in the presence of the resulting salt.
Which substances are produced by neutralization process ?
The neutralization process produces salt and water. The general chemical equation for neutralization is:
Acid+Base→Salt+water
Which are the industrial uses of acids?
Industrial Uses of Acids:
