Questions
Short answer type
1. Define the following terms
i. normality
ii. molarity
iii. equivalent weight
iv. basicity of an acid
2. Give one example each of the following solutions:
i. liquid in solid
ii. gas in solid
iii. liquid in liquid
iv. gas in gas
3. Give the difference between a strong acid and a weak acid. Give one example each.
4. State the methods used to express the concentration of a solution.
5. Give the relation between normality and molarity for an acid as well as a base.
Long answer type
1. Explain the difference between following pairs :
i. molarity and normality
ii. molarity and molality
2. Deduce the normality equation
3. Classify the following compounds as strong acid, strong base, weak acid and weak base giving reasons.
i. H2C2O4 ii. Al(OH)3 iii. HClO4 iv. KOH
4. Acetic acid CH3COOH, contains four H atoms. Even then, it is called a monobasic acid. Why.
5. What is the difference between base and alkali ? Explain it with suitable example.
Give reasons for the following
1. Many times, liquids are preferred to solids for consumption in everyday life.
2. On the basis of three physical states of solute and solvent, there are nine possible combinations of solutions. However, in practice, only seven combinations of solutions are recognized.
3. Equivalent weight is an experimental quantity
4. A normal solution is a standard solution but a standard solution is not a normal solution.
5. Normality equation can be used in titrations.
State whether true or false
1. Number of replaceable H+ ions is called the acidity of the base.
2. When 10 g NaCl is dissolved in 90 g of water, it is called a 10 % solution by mass.
3. Molecular weight of an acid, when expressed in grams, is called its gram equivalent.
4. Acetic acid is a tribasic acid.
5. The product of normality and volume of a solution is constant
Match the following
Fill in the blanks
1. Acidity of a base depends upon --------in a molecule.
2. Normality of a solution is ----------proportional to its volume.
3. A solution of known concentration is called a -------------solution.
4. Molecular weight of an acid or base when divided by its basicity or acidity gives its--------
5. Formation of a solution is a —change.
Multiple choice questions
1) The equivalent weight of crystalline oxalic acid H2C2O4. 2 H2O is —.
a. 63
b. 126
c. 31.5
d. 156.5
2) For H2SO4, the relation between normality and molarity is —.
a. Normality = Molarity
b. Normality = 1 / 2 × Molarity
c. Normality = 2 × Molarity
d. Normality = 3 × Molarity
3) Hydrochloric acid is a —acid
a. weak
b. dilute
c. concentrated
d. strong
4. If 10 g of a solute are dissolved in 1000 g of solvent, the solution is called —solution.
a. 1 Formal
b. 1 Normal
c. 1 Molal
d. 1 Molar
5. For an acid –base titration, which of the following relations, will hold true ?
a. N1V2 = N2V1 b. N1V1= N2V2 c. N1N2 = V1V2 d. N1 /N2 = [ V1/V2 ] 1/2
Answers –1) a 2) c 3) d 4) c 5) b
More Difficult Questions
Problems
a. If 35.26 ml of 0.1126 N H2SO4 requires 38.5 ml of NaOH solution for neutralization, what is the normality of NaOH solution ? ( Answer –0.1031 N )
b. What volme of 0.1162 N HCl solution is required to neutralize 40 ml of NaOH solution that has a concentration of 0.004 g of NaOH per ml of solution? (Answer –34.42 ml )
c. What is the strength in grams per liter of 0.1 N boric acid H3BO3 solution ? ( At. Wt. –B =11, H = 1 , O = 16 )
i. 1.133 ii. 2.066 iii. 6.2 iv. 3.1
d. Soda water is an example of solution of —
i. gas in liquid ii. liquid in gas iii. liquid in liquid iv. solid in liquid
e. While defining molality, the number of moles of solute are divided by —
i. Volume of the solution in liters ii. Volume of the solvent in liters iii. Mass of the solvent in kg iv. Mass of the solution in kg
f. How many grams of Na2CO3 will be required to neutralize 150 ml of 0.223 N sulphuric acid ?
i. 7.092 g ii. 5.319 g iii. 3.546 g iv. 1.773 g
g. A solution of sodium hydroxide was made of such concentration that 50 ml of it was required for complete neutralization of 45.6 ml of HCl. The acid solution contained 0.01892 g HCl per ml of solution. What is the normality of NaOH solution.?
i. 0.1031 N ii. 0.4733 N iii. 0.3010 N iv. 0.4158 N