(a) Concentrated nitric acid oxidises phosphorus to phosphhoric acid according to the following equation;
$P + 5 H N O_{3} (c o n c .) \to H_{3} P O_{4} + H_{2} O + 5 N O_{2}$
If 9.3 g of phosphorus was used in the reaction, calculate;
(i) Number of mles of phosphorus take.
(ii) The mass of phosphoric acid formed.
(iii) The volume of nitrogen dioxide produced at STP.
(b) (i) 67.2 Litres of hydrogen combines with 44.8 letres of nitrogen to form ammonia under specific conditions as:
N_2(g) +3H_2(g) \rightarrow 2NH_3(g)
Calculate the volume of ammonia produced.
What is the other substance, if any that remains in the resultant mixture?
(ii) The mass of $5.6 d m^{3}$ of a certain gas at STP is 12.0 g. Calculate the relative molecular mass of the gas.
(iii) Find the total percentage of Magnesium in magnisum nitrate crystals, $M g (N O_{3})_{2} . 6 H_{2} O .$
$[M g = 24, N = 14, O = 16 a n d H = 1]$

Open in App

Solution

a)

$P plus 5 H N O subscript 3 rightwards arrow H subscript 3 P O subscript 4 plus H subscript 2 O plus 5 N O subscript 2 31 space space space space space space space space space space space space space space space space space space 98 space space space space space space space space space space space space space space space space space space space 5 cross times 22.4 equals 112 l i right parenthesis n o space o f space m o l e s space o f space P equals fraction numerator 9.3 over denominator 31 end fraction equals 0.3 space m o l e s i i right parenthesis m a s s space o f H subscript 3 P O subscript 4 i f space 31 space g m space o f space P space p r o d u c e s space 98 space g m space o f space H subscript 3 P O subscript 4 t h e n 9.3 space g space o f space P space p r o d u c e s equals 98 over 31 cross times 9.3 equals 29.34 equals 29.3 g m i i i right parenthesis v o l u m e space o f space n i t r o g e n space d i o x i d e space a t space S T P i f space 31 g m space o f space P space r e l e a s e space 112 l space o f space N O subscript 2 space a t space S T P t h e n space 9.3 space g m space o f space P space r e l e a s e s equals 112 over 31 cross times 9.3 equals 33.59 equals 33.6 l$

b) $N_{2} (g) + 3 H_{2} (g) \to 2 N H_{3} (g)$

$1 : 3 \to 2$

$i f 1 v o l o f N_{2} g i v e s 2 v o l o f N H_{3}$

then, $44.8 l o f N_{2} g i v e s = 2 \div 1 x 44.8 = 89.6 l$

$i i) v o l u m e o f t h e g a s a t S T P = 5.6 d m^{3} = 5.6 l$

mass of the gas = 12.0gm

$v o l o f S T P = m a s s \div m o l e c u l a r m a s s \times 22.4$

$5.6 l = 12 \div m o l . m a s s \times 22.4$

$m o l e c u l a r m a s s = 12 \times 22.4 \div 5.6 = 48 g m$

iii) Mg(NO3)2.6H2O.
[Mg=24,N=14,O=16andH=1]
$p e r c e n t a g e o f M g = 24 \div 256 \times 100 = 9.37 %$

Suggest Corrections

Similar questions

Q. Concentrate nitric acid oxidises phosphorus to phosphoric acid according to the following equation:

P + 5 H N O_{3} (c o n c .) \to H_{3} P O_{4} + H_{2} O + 5 N O_{2}

9.3 g

of phosphorus was used in the reaction, calculate:
The volume of nitrogen dioxide produced at

S T P

[H = 1, N = 14, P = 31, O = 16]

Q. Concentrate nitric acid oxidises phosphorus to phosphoric acid according to the following equation:

P + 5 H N O_{3} (c o n c .) \to H_{3} P O_{4} + H_{2} O + 5 N O_{2}

9.3 g

of phosphorus was used in the reaction, calculate:
The mass of phosphoric acid formed.

Concentrated nitric acid oxidises phosphorus to phosphoric acid according to the following equation:
$P + 5 H N O_{3} \to H_{3} P O_{4} + 5 N O_{2} + H_{2} O$
If 6.2 g of phosphorus was used in the reaction, calculate:

(a) The number of moles of phosphorus taken and mass of phosphoric acid formed.
(b) Mass of nitric acid consumed at the same time.
(c) The volume of steam produced at the same time if measured at 760 mm Hg pressure and $273^{\circ} C .$

(a) Concentrated nitric acid oxidises phosphorus to phosphoric acid according to the following equation:
P + 5HNO₃ $\overset{}{\to}$ H₃PO₄ + H₂O + 5NO₂
(i) What mass of phosphoric acid can be prepared from 6.2 g of phosphorus?
(ii) What mass of nitric acid will be consumed at the same time?
(iii) What will be the volume of steam at the same time measured at 760 mm Hg pressure and 373°C? (H = 1; N = 14; O = 16; P = 31)

(b) Ammonia may be oxidised to nitrogen monoxide in the presence of a catalyst according to the following equation:
4NH₃ + 5O₂ $\overset{}{\to}$ 4NO + 6H₂O
If 27 litres of reactants are consumed, what volume of nitrogen monoxide is produced at the same temperature and pressure?

67.2

litres of hydrogen combines with

44.8

litres of nitrogen to form ammonia under specific conditions as:

N_{2} (g) + 3 H_{2} (g) \to 2 N H_{3} (g)

Calculate the volume of ammonia produced. What is the other substances, if any, that remains in the resultant mixture?

Join BYJU'S Learning Program