Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 18

EASY

10th ICSE

IMPORTANT

Earn 100

Barium chloride crystals contain $14.8 %$ water of crystallisation. Find the number of molecules of water per molecule.

Important Questions on Mole Concept and Stoichiometry

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 19

Urea is a very important nitrogenous fertilizer. Its formula is

H_{2} N - C (O) - {NH}_{2}

. Calculate the percentage of nitrogen in urea (

C = 12; O = 16; N = 14; H = 1

).

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 20

Determine the formula of the organic compound if its molecule contains

12

atoms of carbon. The percentage compositions of hydrogen and oxygen are

6.48

and

51.42

respectively.

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 21

A compound with empirical formula

{AB}_{2}

, has the vapour density equal to its empirical formula weight. Find its molecular formula.

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 21

A compound with empirical formula

AB

has vapour density three times its empirical formula weight. Find the molecular formula.

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 21

10.47 g

of a compound contained

6.25 g

of metal

A

and rest non-metal

B

. Calculate the empirical formula of the compound (At. wt of

A = 207; B = 35.5

).

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 22

A hydride of nitrogen contains

87.5

per cent by mass of nitrogen. Determine the empirical formula of this compound.

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5E>Q 23

A compound has

O = 61.32 %; S = 11.15 %; H = 4.88 %

and

Zn = 22.65 %

. The relative molecular mass of the compound is

287 a . m . u

. Find the molecular formula of the compound, assuming that all the hydrogen is present as water of crystallisation.

EASY

10th ICSE

IMPORTANT

Selina Icse Concise Chemistry For Class 10>Chapter 5 - Mole Concept and Stoichiometry>EXERCISE-5D>Q 1

Complete the following blanks in the equation as indicated ${CaH}_{2} (s) + 2 H_{2} O (aq) \to Ca {(OH)}_{2} (s) + 2 H_{2} (g)$ .

Moles: $1 mole +$ _____ $\to$ _____ $+$ _____.