At 363 K, the vapour pressure of A is 21 kPa and that of B is 18 kPa. One mole of A and 2 moles of B are mixed. Assuming that this solution is ideal, the vapour pressure of the mixture is ___________ kPa. (Round off to the Nearest Integer).
Answer (integer)
19
Solution
${X_A} = {1 \over {1 + 2}} = {1 \over 3}$<br><br>${X_B} = {2 \over 3}$<br><br>$P_A^o = 21kPa$<br><br>$P_B^o = 18kPa$<br><br>${P_{total}} = P_A^o{X_A} + P_B^o{X_B}$<br><br>$= 21 \times {1 \over 3} + 18 \times {2 \over 3}$<br><br>$= 7 + 12$<br><br>$= 19 kPa$
About this question
Subject: Chemistry · Chapter: States of Matter · Topic: Gas Laws
This question is part of PrepWiser's free JEE Main question bank. 142 more solved questions on States of Matter are available — start with the harder ones if your accuracy is >70%.