Question

26 grams of 2,2 dimethyl hexane( C8H16) under goes combustion. How

much space would the CO2 gas occupy at 26 Celsius and 101.75 kPa?

Answer 1

Answer: The
`CO_(2)` gas occupies a space of 5.57 L at 26 Celsius and 101.75 kPa.

Step-by-step explanation:

Given: Mass = 26 g

Pressure = 101.75 kPa

Convert kPa into atm as follows.

`1 kPa = 0.00986923 atm\\101.75 kPa = 101.75 kPa * (0.00986923 atm)/(1 kPa)\\= 1 atm`

Temperature =
`26^(o)C = (26 + 273) K = 299 K`

Now, moles of a substance is defined as mass of substance divided by its molar mass.

As molar mass of 2,2 dimethyl hexane is 114.23 g/mol. So, its number of moles are calculated as follows.

`No. of moles = (mass)/(molar mass)\\= (26)/(114.23 g/mol)\\= 0.227 mol`

Formula used to calculate the volume is as follows.

PV = nRT

where,

P = pressure

V = volume

n = no. of moles

R = gas constant = 0.0821 L atm/mol K

T = temperature

Substitute the values into above formula as follows.

`PV = nRT\\1 atm * V = 0.227 mol * 0.0821 L atm/mol K * 299 K\\V = 5.57 L`

Thus, we can conclude that the
`CO_(2)` gas occupies a space of 5.57 L at 26 Celsius and 101.75 kPa.