Question

a sample of gas has a volume of 3.40 l at 10.0°c. what will be its volume at 100.0°c, pressure remaining constant?
0.340 l
4.48 l
34.0 l
2.58 l
question 7
9 pts
a sample of gas has a volume of 8.00 l at 20.0°c and 700. torr. what will be its volume at stp?
1.20 l
9.32 l
53.2 l
6.87 l

Explanation:

Step1: Convert temperatures to Kelvin

For the first problem:
Initial temperature \(T_1 = 10.0^{\circ}C+273.15 = 283.15\ K\)
Final temperature \(T_2=100.0^{\circ}C + 273.15=373.15\ K\)
Using Charles's law \(\frac{V_1}{T_1}=\frac{V_2}{T_2}\), where \(V_1 = 3.40\ L\)
\(V_2=\frac{V_1T_2}{T_1}=\frac{3.40\times373.15}{283.15}\approx4.48\ L\)

For the second problem:
Initial temperature \(T_1 = 20.0^{\circ}C+273.15 = 293.15\ K\), \(P_1 = 700\ torr\), \(V_1=8.00\ L\)
At STP, \(P_2 = 760\ torr\), \(T_2 = 273.15\ K\)
Using the combined gas law \(\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}\)
\(V_2=\frac{P_1V_1T_2}{P_2T_1}=\frac{700\times8.00\times273.15}{760\times293.15}\approx6.87\ L\)

Answer:

For the first question: 4.48 L
For the second question: 6.87 L