Question

define chemical equilibrium

68/chem-flash-cards/ A sample of nitrogen gas has a volume of 15.0 ml at a pressure of 0.50 atm. What is the pressure excerted by the gas if the volume is changed to each of the following values? 30.0 ml 50 ml 100 ml 10 L

Answer 1

Chemical equilibrium -

​​​​​​Equilibrium in chemical reactions is defined as a state at which rate of forward reaction occuring becomes just equal to rate to backward reaction occuring. When equilibrium is reached, there is no change in concentrations of reactants and products.

A sample of nitrogen gas has a volume of 15.0 mL at a pressure of 0.50 atm. What is pressure exerted by the gas if the volume is changed to each of the following values ?

30.0 mL

5.0 mL

100 mL

1.0 L

According to Boyle's law, for a given amount of gas, the product PV is always constant. That is :

P_{​​​​​1} V_{​​​​​​1} = P_{​​​​​​2} V₂

(A) 30. 0 mL

Here, P1 = 0.50 atm, V1 = 15 mL, P2 =? & V2 = 30 mL

Thus, putting values to formula, we get,

0.50 atm × 15 mL = P2 × 30 mL

$\large P_{2} = \frac{0.50 \,atm \times 15 \, mL}{30\, mL}$

$\large P_{2} = \frac{0.50 \,atm}{2} = 0.25 \, atm \, \, \, \, (answer 1)$

(B) 5 mL

Here, P1 = 0.50 atm, V1 = 15 mL, V2 = 5 mL, P2 = ?

Thus, putting values to formula,

P1 × V1 = P2 × V2

0.50 atm × 15 mL = 5 mL × P2

$\large P_{2} = \frac{0.50 \, atm \times 15 \, mL}{5\ mL} = 0.50 \, atm \times 3 = 1.5 \, atm$

Thus, answer 2 = 1.5 atm.

(C) 100 mL

Here, P1 = 0.50 atm, V1 = 15 mL, V2 = 100 mL, P2 = ?

Thus,

P1 × V1 = P2 × V2

0.50 atm × 15 mL = P2 × 100 mL

$\large P_{2} = \frac{0.50 \, atm \times 15 \, mL}{100\ mL} = 0.50 \, atm \times 0.15 = 0.075 \, atm$

Hence, Answer 3 = 0.075 atm

(D) 1 L

Here, P1 = 0.50 atm, V1 = 15 mL, V2 = 1 L = 1000 mL, P2 = ?

P1 × V1 = P2 × V2

Thus, putting values to formula,

0.50 atm × 15 mL = P2 × 1000 mL

0.50 atm x 15 ml P2 = = 0.50 atm x 0.015 = 0.0075 atm 1000 ml

Hence, answer 4 = 0.0075 atm.