What temperature does a 0.25 l cylinder containing 0.10 mol of helium gas need to be cooled in order for the pressure to be 253.25 kpa? (given: r = 8.314 l∙kpa/k∙mol

The gas needs to be cooled down to 76.15 K

Explanation:

To calculate the temperature of the gas, we use the equation given by ideal gas, which is:

where,

P = Pressure of the gas = 253.25 kPa

V = Volume of the gas = 0.25 L

n = Number of moles of gas = 0.10 mol

R = Gas constant =

T = Temperature of the gas = ? K

Putting values in above equation, we get:

Hence, the gas needs to be cooled down to 76.15 K

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o