If a gas sample has a pressure of 30.7 kPa at 0.00°C, by how much does the temperature have to decrease to lower the pressure to 28.4 kPa?

1 Answer

Answer:

#T_2 = -20.5^@ "C"#

Explanation:

In this question I assume that the volume is unchanged and therefore, we can use the following law:

#P/T=k#

Then, #(P_1)/(T_1)=(P_2)/(T_2)=>T_2=(T_1)/(P_1)xxP_2#

#=>P_2=("273.15 K")/(30.7cancel("kPa"))xx28.4cancel("kPa") = "252.69 K"#

Therefore, the temperature should be lowered to: #252.69 - 273.15 = - 20.464^@ "C"#

#=> color(blue)(T_2 = -20.5^@"C")# to 3 sig figs.