Chemistry

1.
Method 1 :
CH4 + 4Cl2 → 4HCl + CCl4
No. of moles of CH4­ = 7.014/(12 + 1x4) = 0.4384 mol
No. of moles of Cl­2 = 0.4384 x 4 = 1.754 mol
Mass of Cl2 = 1.754 x (35.5x2) = 124.5 g

Method 2 :

(12 + 1x4) = 16 g of CH4 reacts with (4 x 35.5 x 2) = 284 g of Cl2
Mass of Cl2 = 7.014 x (284/16) = 124.5 g


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2.
Method 1 :
SiO2 + 3C → 2CO + SiC
No. of moles of SiO2 = 7.014/(28.1 + 16x2) = 0.1167 mol
No. of moles of C = 0.1167 x 3 = 0.3501 mol
Mass of C = 0.3501 x 12 = 4.201 g

Method 2 :
SiO2 + 3C → 2CO + SiC
(28.1 + 16x2) = 60.1 g of SiO2 reacts with (3 x 12) = 36 g of C
Mass of C = 7.014 x (36/60.1) = 4.201g

The number of mole of methane is : 7.014/(12.000+1.008*4) = 0.412 mol
The mole ratio of methane : chlorine = 1:4 = 0.412 : 1.648
1.648 * (35.453*2) = 116.853
therefore, 116.853g of chlorine is required.
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The numeber of mole of Silicondioxide is 7.014/(28.086 + 15.999*2) = 0.117 mol
The mole ratio of silicondioxide : carbon = 1:3 = 0.117 : 0.351
Therefore, 0.351 * 12.000 = 4.212g of carbon is required.