(a) Classify the following processes as reversible or irreversible:
(i) Dissolution of sodium chloride.
(ii) Evaporation of water at $373 K$ and $1 a t m$ pressure.
(iii) Mixing of two gases by diffusion.
(iv) Melting of ice without rise in temperature.
(b) When an ideal gas expands in vaccum, there is neither absorption nor revalutions of what? why?

Open in App

Solution

(a) (i) Irreversible,
(ii) Irreversible,
(iii) Irreversible,
(iv) Reversible.
(b) It is because no work is done, i.e, $w = 0, w = - p_{e x t} * Δ V = 0 * Δ V = 0$
In $Δ U = q + w$
$q = 0$ , because gas chamber is insulated $Δ U = 0 + 0 = 0$ .

Suggest Corrections

Similar questions

Q. Assertion :When ice gets converted into water and water into gas, the kinetic energy of the particles increases. Reason: There is rise in temperature during the melting of ice or boiling of water.

Q. Identify the following as reversible or irreversible changes, with reasons:
i) mixing iron filings and sand
ii) shattering of glass
iii) melting of ice

Which of the following reactions are exothermic in nature?

(i) Evaporation of water
(ii) Dissolution of sodium hydroxide in water
(iii) Dilution of sulphuric acid
(iv) Dissolution of ammonium chloride in water
(v) Combustion of methane gas

Question 4

(c) Classify the following processes into physical or chemical changes.
baking of bread, switching of an electric bulb, curdling of milk, dissolving sodium chloride in water, photosynthesis, rusting of iron, evaporation of water, formation of dew, sublimation of camphor, burning of charcoal or LPG, clotting of blood, crystallization of sugar, ripening of fruit, cooking of vegetables, melting of wax.

Q. Calculate the work done in joules when

3

moles of an ideal gas at

27^{o} C

expands isothermally and reversibly from

10

atm to

1

atm.

(1 a t m = 1.013 \times 10^{5} N m^{- 2})

Join BYJU'S Learning Program

(a) (i) Irreversible, (ii) Irreversible, (iii) Irreversible, (iv) Reversible.(b) It is because no work is done, i.e, w=0,w=−pext∗ΔV=0∗ΔV=0In ΔU=q+wq=0, because gas chamber is insulated ΔU=0+0=0.

(a) (i) Irreversible,
(ii) Irreversible,
(iii) Irreversible,
(iv) Reversible.
(b) It is because no work is done, i.e, $w = 0, w = - p_{e x t} * Δ V = 0 * Δ V = 0$
In $Δ U = q + w$
$q = 0$ , because gas chamber is insulated $Δ U = 0 + 0 = 0$ .