Test for Acids, Bases, and Salts

Acids, bases, and salts are essential components of chemistry. A test for acids, bases, and salts is vital for understanding their properties and characteristics. Here are the tests for each of them:

Test for Acids

Acids are substances that release hydrogen ions (H+) in water. Some common acids include hydrochloric acid, sulfuric acid, and nitric acid. To test for acids:

1. Litmus paper test: Dip a strip of blue litmus paper into the solution. If the solution turns red, it is an acid.

2. Methyl orange test: Add a few drops of methyl orange indicator to the solution. If the solution turns pink or red, it is an acid.

3. Phenolphthalein test: Add a few drops of phenolphthalein indicator to the solution. If the solution remains colorless, it is an acid.

Test for Bases

Bases are substances that release hydroxide ions (OH-) in water. Some common bases include sodium hydroxide, potassium hydroxide, and calcium hydroxide. To test for bases:

1. Litmus paper test: Dip a strip of red litmus paper into the solution. If the solution turns blue, it is a base.

2. Methyl orange test: Add a few drops of methyl orange indicator to the solution. If the solution turns yellow or orange, it is a base.

3. Phenolphthalein test: Add a few drops of phenolphthalein indicator to the solution. If the solution turns pink or purple, it is a base.

Test for Salts

Salts are compounds formed by the reaction of an acid and a base. They are known for their characteristic crystal structure and solubility in water. To test for salts:

1. Flame test: Heat a small amount of the salt on a flame. If the flame produces a characteristic color, it is a salt.

2. Solubility test: Add a small amount of the salt to water. If the salt dissolves in water, it is a salt.

In conclusion, testing for acids, bases, and salts is crucial for understanding their properties and characteristics. The tests mentioned above are simple and easy to perform.

Multiple Choice questions
Question 1
When a solution of an acid contains larger amount of acid, it is said to be
(a) Dilute
(b) concentrated
(c) Monobasic
(d) polybasic

Question 2
metals like sodium, potassium and calcium react with an acid to liberate
(a) CO2
(b) NH3
(c)O2
(d)H2

Question 3
Which of the following is a weak acid?
(a) sulphuric acid
(b) hydrochloric acid
(c) acetic acid
(d) nitric acid

Question 4
The chemical formula of baking soda is
(a)Na2Co3
(b) Na2Co3.10H2O
(c) NaHCO3
(d) NaOH

Question 5
Which of the following phenomena occur, when a small amount of acid is added to water?
(a) ionization
(b) Neutralization
(c) Dilution
( d) Salt formations

Question 6
Salt form during reaction of sulphuric acid with copper
(a)Na2SO4
(b) CuSO4
(c) K2SO4
(d) NH4CI

Question 7
CuSO4. K2SO4 is
(a)acid salt
(b) a mixed salt
(c) normal salt
(d) double salt

Question 8
The acid present in vinegar
(a)citric acid
(b) tartaric acid
(c) ascorbic acid
(d) acetic acid

Question 9
Acid reacts with _ of metals to form salt and water.
(a)hydroxide
(b) carbonates
(c) oxides
(d) sulphides

Question 10
Which of these bases is not an alkali?
(a)NaOH
(b) NH4OH
(c) AI (OH)3
(d) all of the are alkalies

Question 11
Which substance is used to purify water
(a)Ammonium chloride
(b) copper sulphate
(c) chlorine
(d) none of these

Question 12
H3PO4 is the example of
(a)hydracids
(b) organic acid
(c) oxyacid
(d) salt

Question 13
To protect tooth decay we are advised to brush our teeth regularly. The nature of the tooth paste commonly used is
(a) acidic
(b) neutral
(c) basic
(d) corrosive

Question 14
Which of the following substance will not give carbon dioxide on treatment with dilute acid?
(a)Marble
(b)Limestone
(c) Baking soda
(d)Lime

Question 15
A compound that reacts with an acid to form a salt and water is called
(a)base
(b) alkali
(c) solution
(d) none of these

Question 16
An indicator is what type of compound?
(a) reducing agent
(b) strong base or acid
(c) weak base or acid
(d) salt

Question 17
H2SO4 can be prepared by reaction of water with
(a)NO2
(b) SO2
(c) N2O
(d) SO3

Question 18
The acidity of Fe(OH)3 is
(a)2
(b) 3
(c) 4
(d) 5

Question 19
The example of olfactory indicators is
(a) Methyl orange
(b) onion
(c) blue litmus
(d) phenolphthalein