Question

[
begin{array}{l}
2 M g+O_{2} longrightarrow 2 M g D
3 M g+N_{2} longrightarrow M g_{3} N_{2}
M g_{3} N_{2}+6 H_{2} O longrightarrow M g(O H)_{2}+2 N H_{3}
end{array}
]
i) To calculate the amount of Magneicum onide (MgO):
( 2 M g+O_{2} longrightarrow )
We Know, ( 2 times 24 g ) of ( M g rightarrow 2 times 40 g ) of ( m g 0 )
( 2 M g O )
( therefore quad 24 g quad 01 )
( u quad longrightarrow> )
[
=40 mathrm{g} & mathrm{Mg} 0
]
(ii) Te Calculate the amount of ( mathrm{Mg}(mathrm{OH})_{2} ) protuced:
[
M_{g_{2} N_{2}}+6 mathrm{H}_{2} mathrm{O} longrightarrow 3 mathrm{Mg}_{2 mathrm{CH}_{2}}+2 mathrm{NH}_{3}
]
we know loog of ( mathrm{Ng}_{2} mathrm{N}_{2} longrightarrow 3 times 58 mathrm{g} ) of ( mathrm{Mg}(mathrm{OH})_{2}+34 mathrm{g} mathrm{MH}_{3} )
( longrightarrow 174 g u_{1}+34 g m u_{3} )
means iog of Mg, Ma
( 17.4 mathrm{g} ) of ( mathrm{Mg}(mathrm{oH})_{2} ).
tij To calculate mass ( % ) of Mg comerted into ( mathrm{Mg}_{3} mathrm{N}_{2} ) :
( 5 mathrm{Mg}+mathrm{O}_{2}+mathrm{N}_{2} longrightarrow mathrm{RNgO}+mathrm{Mg}_{3} mathrm{N}_{2} rightarrow ) comtined
[
begin{array}{l}
5 times 24 g+32 g+28 g rightarrow 22 times 40 g+100 g
text { Lus of conselvation of mass }
end{array}
]
( N_{2} ) is limiting reactant as it is least in mess & which dicmits / controts the product fromion.
( therefore 5 times 24 g ) of Mg (ig 1209 of ( 14 mathrm{g} )
ecadt with ( 28 mathrm{g} ) of ( mathrm{N}_{2} )
[
delta 0,24 g cdot 81 times 99^{4}
]
( (i cdot e) )
( because quad rightarrow}=frac{5.6 times 100}{28}=209 mathrm{MgS} )
( therefore ) it is ( 20 % ). If ( mathrm{Mg}_{3} mathrm{N}_{2} ), produced.

# Stoichiometry - 1 Comprehension: Paragraph for question nos. 47 to 49 24 gm pure sample of magnesium is burned in air to form magnesium oxide and magnesium nitride. When products are treated with excess of H, O,3.4 gm of gaseous NH, is generated according to given reactions Mg +0,- MgO Mg+N, - Mg, N, Mg, N, + 6H,0 - 3Mg (OH), + 2NH, Q.47 Calculate the amount of magnesium oxide (in gm) in products. (C) 16.8 (D)32 (A) 28 (B) 20 Q.48 Calculate the amount of Mg(OH), (in gm) produced in above reaction. (D) 15.8 (C) 23.2 (A) 11.6 (B) 17.4 (D) 40 Q.49 Calculate the mass % of Mg converted into Mg, Ny (C)35 (B) 30 (A) 20

Solution