The empirical formula of a compound is ch. at 200 degrees celsius, 0.242 of this compound occupies 97.2ml at a pressure of 0.740atm. what is the molecular formula of the compound ?

C₁₀H₁₀

Explanation:

We can use the Ideal Gas Law to solve this problem:

       pV = nRT

Since n = m/M, the equation becomes

        pV = (m/M)RT

Data:

p = 0.740 atm

V = 92.7 mL

m = 0.212 g

R = 0.082 16 L·atm·K⁻¹mol⁻¹

T =200 °C

Calculations:

(a) Convert the volume to litres

V = 92.7 mL = 0.0927 L

(b) Convert the temperature to kelvins

T = (200 + 273.15) = 473.15 K

(c) Calculate the molecular mass

The molar mass is 131 g/mol, so the molecular mass is 131 u.

(d) Calculate the empirical formula

EF Mass = (12.01 + 1.008) u  = 13.02 u

The molecular formula is an integral multiple of the empirical formula.

MF = (EF)ₙ

MF = (CH)₁₀ = C₁₀H₁₀

the answer is   c.) 1575 j.

explanation: