10th Class Chemistry Important MCQs Chapter No.1

For the reaction between N₂ and H₂to form NH₃ the unit of Kc is: 

When the magnitude of Kc is very small it indicates:

The rate at which a substance reacts is directly proportional to its active mass and the rate of reaction is directly proportional to the product of active masses of the reacting substances is called:

Which one is not macroscopic characteristic of dynamic equilibrium:

 The characteristic of reversible reaction is :

The gas we exhale during respiration is:

For the reaction:  aA + bB  ⇌   cC + dD  Expression for rate of reverse reaction is...

When the magnitude of K, is very small it indicates:

Plants consume carbon dioxide and release in atmosphere:

The new substances that arc formed in a chemical reaction arc:

Specific rate constant for forward reaction is represented as:

If Q_c < K_c the:

For a reaction between PCI₃ and Cl₂ to form PCI₅, the units of K, are:

Balance equation for the reaction of nitrogen with hydrogen is:

For a reaction PC1₃ + Cl₂     ⇌     PC1₅   , Equilibrium constant expression is:

Specific rate constant for backward reaction is:

A reverse reaction is one that:

The reactions do not stop and take place on both directions at equal rate and attain the equilibrium state is called:

In following reaction the colour of iodine is purple but the product is:

H₂ + I₂   →   2HI

For reaction H₂ + I₂ ⇌ 2HI₃ the unit of Kc:  

For the reaction:   N_2(g) + O_2(g)   ⇌  2NO_(g)  the expression for equilibrium constant is:

Kc is equilibrium constant where:

The reaction in which products do not recombine to form reactants are called:

The major components of atmosphere is:

The reaction will attain the equilibrium if:

The correct representation of reversible reaction between 112 and 12 is:

Molar concentration (mol dm^-3) is expressed as:

The lives of aquatic plants and animals depend on the oxygen which is:

The value of Kc depends only on:

Dynamic means:

 At dynamic equilibrium state:

For the reaction,   2CO + O₂  ⇌    2CO₂   The value of K_c is:

Reaction goes from right to left if:

CaCO₃ →  CaO +  ?  

 During given reaction the gas evoked is:

Describe the relationship between active masses of the reactants and rate of reaction.

The product of following reaction is:            2H2 + O2   →    ?

Which one of the following statement is not correct about active mass?

For the reaction:  aA + bB  ⇌   cC + dD Expression for forward reaction according to law of mass action is:

For the reaction,    2A_(g) + 13_(g)  ⇌ 3C_(g)     the expression for the equilibrium constant is:

In the lime kiln, the reaction:
CaCo_3(s) -----------> CaO_(s) + CO_2(g)     goes to completion because.

For the reaction: N₂ + 3H₂ ⇌ 2NH₃   the expression for rate constant is

Macroscopic characteristic of backward reaction is:

The percentage of oxygen in atmosphere is:

For the reaction:    N₂O₄        ⇌    2N₂ value of K_c is:

The reaction in which all the reactants arc converted into products:

At chemical equilibrium state:

Law of mass action is given by:

Macroscopic characteristic of forward reaction is:

Unit of K_c for reaction N₂ + 3H₂ ⇌ 2NH₃  is:

The gas we inhale during breathing is:

At dynamic equilibrium:-

If numerical value of K_c is neither small nor large then:

When a system is at equilibrium states:

When the magnitude of K_c is very large it indicates:

The Product of the reaction CaO + CO₂  →  ?

In an irreversible reaction dynamic equilibrium:

For [H₂] =0.05 mol dm^-3    [I₂] = 0.06 mol din^-3 and (HI) = 0.49 mol dm^-3 the Value of K_c is:

At equilibrium state when reaction ceases to proceed, it is called:

When the magnitude of K_c is very large it indicates:

The characteristic of irreversible reaction:

The substances that combine in a chemical reaction are called:

For the reaction:   aA + bB  ⇌   cC + dD  the expression for chemical equilibrium constant is:

Reactions which have comparable amounts of reactants and products at equilibrium state have:

If the numerical value of Q_c (reaction quotient) is less than K_c then;

Nitrogen and hydrogen were together to make ammonia:

N₂ +3H₂ ⇌  2NH₃           Kc = 2.86 mol ^-2 dm ⁶

What will be present in the equilibrium mixture?

THe Characteristics of reversible reactions are the following except.......

The percentage of nitrogen in atmosphere is:

Oxidation of carbon monoxide goes to completion at: