Question

The reaction between nitrogen and hydrogen is used to produce ammonia (NH3).

Give the balanced chemical reaction

Draw the electron dot structures of all these chemical species.

What is the predicted VSEPR geometry of all these chemical species?

When 450. g of hydrogen was reacted with excess nitrogen; 1575 g of ammonia were produced. What is the percent yield of this reaction?

Assuming that only the product is collected, what is the pressure inside of a 10.0 L tank at 298 K?

Answer 1

First, add the species

N2 + H2 = NH3

balance N

a)

N2 + H2 = 2NH3

balance H

N2 + 3H2 = 2NH3

add phases

N2(g) + 3H2(g) = 2NH3(g)

b)

Draw electrn dot structureS:

c)

predicted goemetry:

N2 molecule = must be linear, since it is bimolecular AND nonpolar molecule, exec 180° angle

H2 molecule = must be linear, since it is bimolecular AND nonpolar molecule, exec 180° angle

NH3 mlecule = must be POLAR, since there is a lone pair on top o fNitrogen which ushes/repeals the Hydrogen bonding

This will have therefore, a trigonal pyramid angles are about 107-109° approx

d)

m = 450 g of H2 gas react with excess N2

mol of H2 = mass/MW = 450/ 2 = 225 moles of H2

3 mol of H2 = 2 mol of NH3

225 moles = 2/3*225 = 150 mol of NH3

now, calcualte mass of NH3

mass = mol*MW = (150)*17 = 2550 g of NH3

% yield = real / theoretical * 100% = 1575/2550*100 = 61.764 %

d)

Apply Ideal gas law and calculate pressure

Apply Ideal Gas Law,

PV = nRT

where

P = absolute pressure

V = total volume of gas

n = moles of gas

T = absolute Tmperature

R = ideal gas constant

P = nRT/V

P = (150 )(0.082)(298)/(10)

P = 366.54 atm