Determine the identity of a sample of gas at STP conditions, with a mass of 120.00 grams that occupies 67.2 L. a) N2
b) Ar
c) He
d) Ne
explain your answer

b) Ar

Explanation:

Given data:

Mass of sample gas = 120.00 g

Volume of gas = 67.2 L

Identity of gas = ?

Solution:

We will calculate the molar mass do identify the sample:

Number of moles of gas:

PV = nRT

1 atm×67.2 L = n×0.0821 atm.L/mol.K×273 K

67.2 atm.L = n × 22.42atm.L/mol

n = 67.2 atm.L / 22.42atm.L/mol

n = 3 mol

Molar mass of gas:

Number of moles = mass/molar mass

Molar mass = 120.00 g/3 mol

Molar mass = 40 g/mol

The given sample of a gas is Ar.

mechanics (greek   is that area of science concerned with the behaviour of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment. the scientific discipline has its origins in ancient greece with the writings of aristotle and archimedes[1][2][3] (see history of classical mechanics and timeline of classical mechanics). during the early modern period, scientists such as galileo, kepler, and newton laid the foundation for what is now known as classical mechanics. it is a branch of classical physics that deals with particles that are either at rest or are moving with velocities significantly less than the speed of light. it can also be defined as a branch of science which deals with the motion of and forces on objects. the field is yet less widely understood in terms of quantum theory.

explanation: