A gas mixture is composed of three different gases. The first gas in the mixture has a pressure of 0.35 atm. The second gas in the mixture has a pressure of 0.20 atm. The third gas in the mixture has a pressure of 0.65 atm. What is the total pressure of the gas mixture? (answer with correct significant figures and units)

1.20atm

Explanation:

Given parameters:

Partial pressure of gas 1 = 0.35atm

Partial pressure of gas 2  = 0.20atm

Partial pressure of gas 3  = 0.65atm

Unknown:

Total pressure of the gas mixture = ?

Solution:

To solve this problem, we need to recall and understand the Dalton's law of partial pressure.

Dalton's law of partial pressure states that "the total pressure of a mixture of gases is equal to the sum of the partial pressure of the constituent gases".

    Total pressure  =Pressure of gas(1 + 2 + 3)

The partial pressure is the pressure a gas would exert if it alone occupied the volume of the gas mixture.

Now we substitute;

      Total pressure  = (0.35 + 0.20 + 0.65)atm  = 1.20atm

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.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.