A 256 mL sample of HCl gas is in a flask where it exerts a force (pressure) of 67.5 mmHg. What is the pressure of the gas if it were transferred to a 135 mL flask

The pressure in the new flask would be if the here acts like an ideal gas.  

Explanation:

Assume that the sample here acts like an ideal gas. By Boyle's Law, the pressure of the gas should be inversely proportional to its volume .

For example, let the initial volume and pressure of the sample be and . The new volume and pressure of this sample shall satisfy the equation: .

In this question,

The goal is to find the new pressure of this gas, .

Assume that this sample is indeed an ideal gas. Then the equation should still hold. Rearrange the equation to separate the unknown, . Note: make sure that the units for and are the same before evaluating. That way, the unit of

.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.