Question

In an isothermal and reversible process, 1.6 × 10-2 kg O₂ expands from 10 dm³ to 100 dm³ at 300 K, work done in the process is ______. (R = 8.314 JK^-1 mol^-1).

Options

• - 5744 J

• - 1436 J

• - 2872 J

• - 4308 J

Answer 1

In an isothermal and reversible process, 1.6 × 10-2 kg O₂ expands from 10 dm³ to 100 dm³ at 300 K, work done in the process is - 2872 J.

Explanation:

V₁ = 10 dm³, V₂ = 100 dm³, T = 300K,

R = 8.314 JK^-1 mol^-1, `"m"_("o"_2) = 1.6 xx 10^-2 "kg" = 16 "g"`

`therefore "n" = ("m"_("o"_2))/("M"_("o"_2)) = 16/32` = 0.5 mol

For isothermal and reversible process,

`"W"_"max" = - 2.303 "nRT" log_10 "V"_2/"V"_1`

`therefore "W"_"max" = - 2.303 xx 0.5 xx 8.314 xx 300 xx log_10 = 100/10`

= - 2872 J