Does the number of moles of reaction products increase, decrease … - Vidyadip

Question

Does the number of moles of reaction products increase, decrease or remain same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?
(a) $PCl _5(g) \rightleftharpoons PCl _3(g)+ Cl _2(g)$
(b) CaO (s) $+ CO _2$ (g) $\rightleftharpoons CaCO _3$ (s)
(c) $3 Fe ( s )+4 H _2 O ( g ) \rightleftharpoons Fe _3 O _4(s)+4 H _2(g)$

✓

Answer

According to Le Chatelier's principle :
(a) On reducing pressure rate of forward reaction increases. Hence, number of moles of product increases.
(b) On reducing pressure, rate of backward reaction increases. Hence moles of product decreases.
(c) There will be no effect of pressure on this reaction as number of moles remains constant ( $\Delta n ( g )$ $=0$ ).

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "2 Marks Questions" from PART - 1 CH - 6 Equilibrium→PART - 1 CH - 6 Equilibrium — all question types→Chemistry STD 11 Science question papers→Rajasthan Board STD 11 Science question papers→Rajasthan Board question paper generator→

Similar questions

Assign oxidation number to the underlined elements in the following species:

H₂S₂O₇

Enthalpies of formation of $CO ( g ), CO _2(g)$, $N _2 O ( g )$ and $N _2 O _4(g)$ are $-110,-393,81$ and 9.7 kJ $mol ^{-1}$ respectively. Find the value of $\Delta_{ r } H$ for the reaction :
$N _2 O _4(g)+3 CO ( g ) \rightarrow N _2 O ( g )+3 CO _2(g)$

One mole of $H _2 O$ and one mole of CO are taken in 10 L vessel and heated to 725 K . At equilibrium $40 \%$ of water (by mass) reacts with CO according to the equation,
$H _2 O ( g )+ CO ( g ) \rightleftharpoons H _2(g)+ CO _2(g)$
Calculate the equilibrium constant for the reaction.

Among the elements of the third period Na to Ar, pick out the element:

With highest first ionisation enthalpy.
With largest atomic radius.
Which is most reactive non-metal.
Which is most reactive metal.

Use the periodic table to answer the following questions.
(a) Identify an element with five electrons in the outer subshell.
(b) Identify an element that would tend to lose two electrons.
(c) Identify an element that would tend to gain two electrons.
(d) Identify the group having metal, non-metal, liquid as well as gas at the room temperature.

Classify the following species into Lewis acids and Lewis bases and show how these act as Lewis acid/base:
a. $OH ^{-}$
b. $F ^{-}$
c. $H ^{+}$
d. $BCl _3$

Write redox couples involved in the reactions (i) to (iv) given in question 34.

Give the IUPAC names of each of the following:

→

A gas absorbs a photon of 355nm and emits at two wavelengths. If one of the emissions is at 680nm, at what place the other emission occur?

How would you explain the fact that the first ionization enthalpy of sodium is lower than that of magnesium but its second ionization enthalpy is higher than that of magnesium?