Match the items in column A with the items in column B. Column a Column b 1. The mass of one atomic mass unit a. one 2. The number of gram-atoms of carbon in 1 mole of mass calcium hydrogen carbonate b. gram-atomic mass 3. The mass of H 2 produced when 0.5 mole of zinc reacts with an excess of dil. HCl c. 1 . 66 × 10 - 24 g 4. The mass in grams of Avogadro's number of atoms of a substance is called d. 3 . 01 × 10 23 5. The number of molecules in 35.5 g of Cl 2 e. 6 . 022 × 10 23 6. The number of molecules in 64 g of SO 2 . f. 1 . 43 × 10 - 21 g 7. The mass of molecule of a compound having formula C 70 H 22 . g. 1 g

One atomic mass unit is equal to the one-twelfth mass of carbon-12 atom that is equal to 1 . 66 × 10 - 24 g . The number of gram-atoms of carbon in 1 mole of mass calcium hydrogen carbonate is one because one carbon atom is present in calcium hydrogen carbonate. The mass of H 2 produced when 0 . 5 mole of zinc reacts with an excess of dilute HCl is 1 g . Number of moles= Given mass Molar mass Mass= 0 . 5 × 2 = 1 g The mass in grams of Avogadro's number of atoms of a substance is called gram atomic mass. The number of molecules in 35 . 5 g of Cl 2 is 3 . 01 × 10 23 . Number of molecules= Number of moles × Avogadro number = 35 . 5 71 × 6 . 022 × 10 23 = 3 . 01 × 10 23 The number of molecules in 64 g of SO 2 6 . 022 × 10 23 Number of molecules=Number of moles × Avogadro number = 64 64 × 6 . 022 × 10 23 = 6 . 022 × 10 23 The mass of molecule of a compound having formula C 70 H 22 1 . 43 × 10 - 21 g Column a Column b 1. The mass of one atomic mass unit c. 1 . 66 × 10 - 24 g 2. The number of gram-atoms of carbon in one mole of mass calcium hydrogen carbonate a. one 3. The mass of H 2 produced when 0 . 5 mole of zinc reacts with an excess of dil. HCl g. 1 g 4. The mass in grams of Avogadro's number of atoms of a substance is called b. gram-atomic mass 5. The number of molecules in 35 . 5 g of Cl 2 d. 3 . 01 × 10 23 6. The number of molecules in 64 g of SO 2 . e. 6 . 022 × 10 23 7. The mass of molecule of a compound having formula C 70 H 22 . f. 1 . 43 × 10 - 21 g

E M B I B E

LIVING SCIENCE CHEMISTRY 9>Chapter 3 - Atoms and Molecules>EXERCISES>Q D

EASY

9th CBSE

IMPORTANT

Earn 100

Tabulate the difference between gram-atom and gram-molecule.

Important Questions on Atoms and Molecules

MEDIUM

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 3 - Atoms and Molecules>EXERCISES>Q D

Tabulate the difference between molecular formula and empirical formula.

HARD

9th CBSE

IMPORTANT

LIVING SCIENCE CHEMISTRY 9>Chapter 3 - Atoms and Molecules>EXERCISES>Q E

Match the items in column A with the items in column B.

Column a	Column b
1. The mass of one atomic mass unit	a. one
2. The number of gram-atoms of carbon in 1 mole of mass calcium hydrogen carbonate	b. gram-atomic mass
3. The mass of $H_{2}$ produced when 0.5 mole of zinc reacts with an excess of dil. $HCl$	c. $1.66 \times 10^{- 24} g$
4. The mass in grams of Avogadro's number of atoms of a substance is called	d. $3.01 \times 10^{23}$
5. The number of molecules in 35.5 g of ${Cl}_{2}$	e. $6.022 \times 10^{23}$
6. The number of molecules in 64 g of ${SO}_{2}$ .	f. $1.43 \times 10^{- 21} g$
7. The mass of molecule of a compound having formula $C_{70} H_{22}$ .	g. $1 g$