Partial Pressure worksheet

1. Total pressure: 1.27 Pa

1. Add up the partial pressures. Dalton's law says they make up the total pressure

   $P$$=1+0.26+0.0078+0.0003$$=1.2681\text{\hspace{0.17em}Pa}$

2. Divide each gas's pressure by the total to get its share, the mole fraction χ (first gas shown)

   $\mathrm{\chi ₁}$$=\frac{1}{1.2681}$$=0.788581$

2. Total pressure: 0.85 kPa

1. Add up the partial pressures. Dalton's law says they make up the total pressure

   $P$$=0.65+0.19+0.01+0.0005$$=0.8505\text{\hspace{0.17em}kPa}$

2. Divide each gas's pressure by the total to get its share, the mole fraction χ (first gas shown)

   $\mathrm{\chi ₁}$$=\frac{0.65}{0.8505}$$=0.764256$

3. Partial pressure: 0.18 MPa

1. Each gas gives its share of the push. So multiply its share of the molecules (the mole fraction) by the total pressure

   $\mathrm{Pᵢ}$$=0.18\times 1\text{\hspace{0.17em}MPa}$$=0.18\text{\hspace{0.17em}MPa}$

4. Total pressure: 1 kPa

1. Add up the partial pressures. Dalton's law says they make up the total pressure

   $P$$=0.7808+0.2095+0.0093+0.0004$$=1\text{\hspace{0.17em}kPa}$

2. Divide each gas's pressure by the total to get its share, the mole fraction χ (first gas shown)

   $\mathrm{\chi ₁}$$=\frac{0.7808}{1}$$=0.7808$

5. Total pressure: 1.42 bar

1. Add up the partial pressures. Dalton's law says they make up the total pressure

   $P$$=1.1+0.31+0.008+0.0005$$=1.4185\text{\hspace{0.17em}bar}$

2. Divide each gas's pressure by the total to get its share, the mole fraction χ (first gas shown)

   $\mathrm{\chi ₁}$$=\frac{1.1}{1.4185}$$=0.775467$

6. Total pressure: 0.99 Torr

1. Add up the partial pressures. Dalton's law says they make up the total pressure

   $P$$=0.78+0.2+0.009+0.0003$$=0.9893\text{\hspace{0.17em}Torr}$

2. Divide each gas's pressure by the total to get its share, the mole fraction χ (first gas shown)

   $\mathrm{\chi ₁}$$=\frac{0.78}{0.9893}$$=0.788436$

7. Partial pressure: 0.25 hPa

1. Find the gas's share of the molecules (the mole fraction χ): its moles ÷ the total moles

   $\chi$$=\frac{2\text{\hspace{0.17em}mol}}{8\text{\hspace{0.17em}mol}}$$=0.25$

2. Each gas gives its share of the push. So multiply its share of the molecules (the mole fraction) by the total pressure

   $\mathrm{Pᵢ}$$=0.25\times 1\text{\hspace{0.17em}hPa}$$=0.25\text{\hspace{0.17em}hPa}$

8. Total pressure: 0.93 inHg

1. Add up the partial pressures. Dalton's law says they make up the total pressure

   $P$$=0.7+0.22+0.013+0.0003$$=0.9333\text{\hspace{0.17em}inHg}$

2. Divide each gas's pressure by the total to get its share, the mole fraction χ (first gas shown)

   $\mathrm{\chi ₁}$$=\frac{0.7}{0.9333}$$=0.750027$

9. Partial pressure: 0.28 inHg

1. Each gas gives its share of the push. So multiply its share of the molecules (the mole fraction) by the total pressure

   $\mathrm{Pᵢ}$$=0.275\times 1\text{\hspace{0.17em}inHg}$$=0.275\text{\hspace{0.17em}inHg}$

10. Partial pressure: 0.2 Torr

1. Find the gas's share of the molecules (the mole fraction χ): its moles ÷ the total moles

   $\chi$$=\frac{1\text{\hspace{0.17em}mol}}{10\text{\hspace{0.17em}mol}}$$=0.1$

2. Each gas gives its share of the push. So multiply its share of the molecules (the mole fraction) by the total pressure

   $\mathrm{Pᵢ}$$=0.1\times 2\text{\hspace{0.17em}Torr}$$=0.2\text{\hspace{0.17em}Torr}$