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The pH of 10-3 mol dm-3 of an aqueous solution of H2SO4 is

1. 3
2. 2.7
3. 2
4. 1.5

✅ Correct Answer: 2

Kc value has

1. No units
2. Units
3. Both a & b
4. None

✅ Correct Answer: 3

If a buffer solution of higher pH than seven is to be made we use

1. Strong acid and strong base
2. Weak acid and strong base
3. Weak acid and strong base
4. Weak acid and its salt with strong base

✅ Correct Answer: 4

Sodium benzoate and benzoic acid are mixed in equimolar ration to form buffer if pKa is 2 what will be the pH?

1. 0
2. 1
3. 2
4. any one

✅ Correct Answer: 3

AgCl dissolved with conc (2x10-2) Ksp will be

1. 3.6 x 10-6
2. 3.6 x 10-5
3. 7.2 x 10-6
4. 4 x 10-4

✅ Correct Answer: 4

In which of the following equilibria will Kc and Kp have the same value?

1. PCI5 = PCI3 + Cl2
2. N2 + 3H2 = 2NH
3. 2CO + O2 = CO2
4. N2 + O2 = 2NO

✅ Correct Answer: 4

Which of the following will not change the concentration of ammonia at the equilibrium ?

1. Increase of pressure
2. Increase of volume
3. Addition of catalyst
4. Decrease of temperature

✅ Correct Answer: 3

pH of an aqueous solution is 5.5. The hydroxyl ion conc. In the solution would be

1. ?5.5
2. ?8.5
3. 10-8.5
4. 10

✅ Correct Answer: 3

For a reaction involving only gases at 25?C the equilibrium constant can be expressed in terms of molarity Ke or partial pressure Kp. Which is true about the numerical value of Kp?

1. Kc is generally greaer than Kp
2. Kc is generally less than Kp
3. Kc is generally equal to Kp
4. Kc is equal to Kp if the total moles of reactants and products are equal

✅ Correct Answer: 4

Which of following is not a base

1. KOH
2. NH3
3. PH3
4. BF3

✅ Correct Answer: 4

Which set of solutes will form a buffer when dissolved in water to make 1 litter of solution?

1. 0.0002M HCI
2. 0.2 mole of NaCI with 0.2 mole of HNO3
3. 0.4 mole of CH3COOH with 0.4 mole of NaOH
4. 0.4 mole of NH3 with 0.2 mole of HCI

✅ Correct Answer: 4

Which one of the following aqueous solutions will be basic?

1. NaCI
2. Na2SO4
3. Na2CO3
4. FeCl3

✅ Correct Answer: 3

The value of Kw in an acidic aquueous solution at 298 K is

1. >10-14
2. <10-14
3. 101?
4. 10-1?

✅ Correct Answer: 4

Reaction which proceeds in both directions is called

1. reversible
2. irreversible
3. spontaneous
4. non-spontaneous

✅ Correct Answer: 1

Chemical equilibrium state is

1. dynamic state
2. static state
3. free state
4. unidirectional state

✅ Correct Answer: 1

Conversion of reactant into product in unit time is called

1. rate of forward reaction
2. rate of backward reaction
3. rate constant
4. rate co-efficient

✅ Correct Answer: 1

At start of reaction the concentration of reactants is

1. high
2. low
3. according to Kc
4. constant

✅ Correct Answer: 1

Unit of Kc is

1. moles2dm+6
2. moles-2dm+6
3. moles+2dm-6
4. Kc may or may not have units

✅ Correct Answer: 4

In case of gases Kc is replaced by

1. Ka
2. Kb
3. Kp
4. K

✅ Correct Answer: 3

Rate expression for ammonia synthesis is

1. Kc=x2/(a-x)(b-x)
2. Kc=x2/v(a-x)
3. Kc=4x2/(a-2x)2(b-x)
4. Kc=4x2v2/(a-x)(b-3x)3

✅ Correct Answer: 4

When the value of Kc is very small then

1. reaction is at start
2. product conc. Is maximum
3. reactant conc. Is minimum
4. reaction is completed

✅ Correct Answer: 2

Catalyst used to speed up the reaction of ammonia synthesis is

1. V2O5
2. V2O5 and Pt
3. Fe
4. Pieces of Fe crystals are embedded in fused mixture of MgO Al2O3 and SiO2

✅ Correct Answer: 4

Temperature for preparation of SO3 is

1. 400-500?C
2. 400?C
3. 600?C
4. 200?C

✅ Correct Answer: 1

By the addition of base in waterpH will be

1. more than 7
2. less than 7
3. equal to 7
4. no effect

✅ Correct Answer: 1

Idea of pH and pOH was put forward by

1. Gibbs
2. Einstein
3. Sorenson
4. Chadwick

✅ Correct Answer: 3

Negative log of mular concentration of H+ ions is called

1. pH
2. pOH
3. pKa
4. pKw

✅ Correct Answer: 1

Ka<10-3 means

1. Very strong base
2. Very weak acid
3. Very strong acid
4. Very strong salt

✅ Correct Answer: 2

Any substance which accepts H+ is base favours the concept

1. Lowrys
2. Lewis
3. Arrhenius
4. None of these

✅ Correct Answer: 1

Conjugated base of a weak acid is

1. weak
2. strong
3. moderately weak
4. unstable

✅ Correct Answer: 2

When sparingly soluble salt is in equilibrium with molar concentration of its oppositely charged ion when the product is called

1. common ion effect
2. solubility product
3. dissociation constant
4. dissociation constant for an acid

✅ Correct Answer: 2

Solution having the property of a very little change in pH on adding a small amount of strong acid or base is called

1. buffer solution
2. normal solution
3. standard solution
4. neutral solution

✅ Correct Answer: 1

Addition of CH3COOH and CH3COONa gives in water

1. Standard solution
2. buffer solution
3. acidic buffer solution
4. both b & c

✅ Correct Answer: 4

Which one of the following is a buffer solution?

1. brine
2. blood
3. glue
4. solution of CuSO4

✅ Correct Answer: 2

Solubility of any salt can be determined from

1. Ka
2. Kb
3. Kc
4. Ksp

✅ Correct Answer: 4

The pH of human blood is

1. 7
2. 7.35
3. 7.5
4. 7.8

✅ Correct Answer: 2

By decreasing the pressure the reaction will go to that direction where

1. volume is decreased
2. volume increased
3. heat absorbed
4. no. of moles of specie decreased

✅ Correct Answer: 2

Equilibrium state is achieved quickly by the addition of.

1. reactants
2. acid
3. base
4. catalyst

✅ Correct Answer: 4

The rate of reaction

1. Increases as the reaction proceeds
2. Decreases as the reaction proceeds
3. Remains the same as the reaction proceeds
4. May decrease or increase as the reaction proceeds

✅ Correct Answer: 2

The addition of a catalyst to the reaction system

1. Increases the rate of forward reaction only
2. Increases the rate of reverse reaction
3. Increases the rate of forward but decreases the rate of backward reaction
4. Increases the rate of forward as well as backward reaction equally

✅ Correct Answer: 4

The specific rate constant of a first order reaction depends on the

1. Time
2. Concentration of the reactant
3. Temperature
4. Concentration of the product

✅ Correct Answer: 3

On increasing the temperature the rate of reaction increases mainly because

1. The activation energy of the reaction increases
2. Concentration of the reacting molecules increases
3. Collision frequency increases
4. None of these

✅ Correct Answer: 3

?d[N2O5]/dt represents

1. Rate of formation of N2O5
2. Rate of decomposition of N2O5
3. order of the reaction
4. none

✅ Correct Answer: 2

The value of activation energy is primarily determined by

1. Temperature
2. Effective collision
3. Concentration of reactants
4. Chemical nature of reactants and products

✅ Correct Answer: 2

Sum of exponents of molar concentration is called

1. Order of reaction
2. Molecularity
3. Rate of reaction
4. Average of reaction

✅ Correct Answer: 1

Spontaneous reactions are

1. Moderate
2. Slow
3. Fast
4. not natural

✅ Correct Answer: 3

In rate expression the concentration of reactants is negative. It shows

1. Concentration of reactant does not change
2. Concentration of product increases
3. Concentration of reactant decreases
4. Concentration of reactant increases

✅ Correct Answer: 3

Unit of rate of reaction is

1. Moles dm-3 sec-1
2. Moles dm-3
3. Moles sec-1
4. Mol-1 dm3 sec-1

✅ Correct Answer: 1

When a graph is plotted between 1/T on X-axis and log k on y-axis a straight line is obtained with a negative slope which has two end in

1. I and II quadrant
2. II and III quadrant
3. III and IV quadrant
4. II and IV quadrant

✅ Correct Answer: 4

Rate of disappearance of reactant is equal to

1. Rate of reaction
2. Rate of formation of product
3. Energy released during reaction
4. a and b

✅ Correct Answer: 1

Rate of reaction when concentration of reactants are taken as unity is called

1. Arrhenius constant
2. Molecularity
3. Specific rate constant
4. Ideal rate constant

✅ Correct Answer: 3

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