Sarthaks APP
0 votes
623 views
in States of Matter - Gas and Liquid by (50.0k points)

4.05 ml of phosphorus vapour weighs 0.0625g at 546 °C and 0.1 bar pressure. What is the molar mass of phosphorus?

1 Answer

+1 vote
by (51.1k points)
selected by
 
Best answer

Given, P = 0.1 bar
V = 34.05 mL = 34.05 × 10-3L
= 34.05 × 10-3 dm3
R = 0.083 bar dm3K-1mol-1
T = 546°C = (546 + 273) K = 819 K
The number of moles (n) can be calculated using the ideal gas equation as:
From the gas equation
PV = w ,RT/M,we get
M = w. RT/ PV      …(1)
Substituting the given values in the equation (1), we get M = (0.0625 / 0.1 × 34.04) × 82.1 × 819 = 124.75 g/mol
Hence, the molar mass of phosphorus is 124.75 g mol-1.

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

...