All Free Chemistry MCQs with Answers
Every Chemistry question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
13,720 questions · page 562 of 686
- A. It is a metal
- B. It forms positive ions
- C. It may form ionic bond
- D. It belongs to p _ block
Explanation: Elements having low ionization energy usually belong to s-block and high ionization energy to p- block.
Correct answer: It belongs to p _ block- A. Triangular planar
- B. Tetrahedral
- C. Linear
- D. Distorted tetrahedral.
Explanation: SOCl2 has disordered tetrahedral structure .This geometry is attributed to the effects of the lone pair on the central sulfur(IV) center.
Correct answer: Distorted tetrahedral.- A. HC1O3
- B. H2S
- C. H3O+
- D. PbCI4
Explanation: In PbCI4 the central atom Pb has no lone pair of electrons.
Correct answer: PbCI4- A. SO-24
- B. ClO-4
- C. NH+4
- D. XeF4
Explanation: All of the other molecules have tetrahedral shape whereas XeF4 has square planar shape with bond angle 90° or 180° .
Correct answer: XeF4- A. CH4
- B. KCN
- C. H2
- D. KCl
Explanation: Option B is correct.The compound that contains both ionic and covalent bonds is KCN.
Correct answer: KCN11226. Choose the correct option.
- A. It was a crisis for whom he was totally unprepared.
- B. It was a crisis for which he totally was unprepared.
- C. It was a crisis for which he was totally unprepared.
- D. It was crisis for which he was totally unprepared.
Explanation: This option is correct. "Which" is the correct relative pronoun to introduce the clause referring to the crisis.
Correct answer: It was a crisis for which he was totally unprepared.- A. We have a motto: live life to the full.
- B. We have a motto, live life to the full.
- C. We have a motto; live life to the full.
- D. We have a motto live life to the full
Explanation: This sentence correctly uses a colon to introduce a quotation or a statement that explains or illustrates the preceding clause.
Correct answer: We have a motto: live life to the full.- A. The amount of product formed.
- B. Product of the molar concentration of reactants.
- C. The initial concentration of reactants.
- D. Catalyst.
- E. Pressure.
Explanation: The speed at which the reactants are converted to products is called the rate of reaction.
Correct answer: Product of the molar concentration of reactants.- A. The values of Kp and Kc are different
- B. The value of Kp is greater than Kc
- C. The value of Kc is greater than Kp
- D. The values of Kp and Kc are the same
Explanation: If the difference in n is zero, the Kp = Kc.
Correct answer: The values of Kp and Kc are the same- A. The value of Kp falls, with a rise in temperature
- B. The value of Kp falls with an increase in pressure
- C. The value of Kc is equal to Kp
- D. The value of Kc remains constant with rise in temperature.
Explanation: The reaction is exothermic, With increase in temperature the reaction moves towards the reactants side increasing the partial pressure of…
Correct answer: The value of Kp falls, with a rise in temperature- A. Lowering temperature
- B. Decreasing pressure
- C. A catalyst
- D. All of these
Explanation: Reason: Catalysts are substances that lower the activation energy which results in an increase in rate of reaction.
Correct answer: A catalyst11232. The rate of reaction _.
- A. Increases as reaction proceeds
- B. Decreases as reaction proceeds
- C. Remains unchanged
- D. None of these
Explanation: As the reaction proceeds, the rate of reaction is slowing down with time because at the start, the rate of reaction is fast due to…
Correct answer: Decreases as reaction proceeds- A. Ag+ and NO3- only.
- B. Ag+and NO3- and Ba+2 only.
- C. NO3- and Ba+2 only.
- D. CI- and NO3- and Ba+2 only.
Explanation: 2AgNO3+BaCl2→2AgCl + Ba+2+NO3-. If AgNO3 is in excess then filterate contains Ba+2, NO3- and Ag+.
Correct answer: Ag+and NO3- and Ba+2 only.- A. S=(Ksp/ 128 )1/4
- B. S=(27Ksp)1/3
- C. S=(Ksp/ 27)1/4
- D. S=(Ksp/ 81)1/4
Explanation: AB3 ⇌ A+3+3 B-1s s 3sFor a compound having four ionsKsp=[A+3][B-1]3Ksp (s).(3s)3Ksp=27s4s = (Ksp/27)1/4
Correct answer: S=(Ksp/ 27)1/4- A. Weak acid and its salt with strong base.
- B. Weak base and its salt with strong acid.
- C. Strong acid and its salt with weak base.
- D. Strong base and its salt with strong acid.
Explanation: By mixing a weak base and a salt of it with a strong acid. Such solutions will give basic bufers with pH more than 7.
Correct answer: Weak base and its salt with strong acid.- A. May or may not have a unit
- B. Depend upon equilibrium concentrations
- C. Thermodynamic property
- D. All of these
Explanation: All of the above mentioned properties are true for Kc. As it is a measure of the ratio of concentrations of products and reactants at…
Correct answer: All of these- A. Kf =ke
- B. [P] = [R]
- C. Rf = Rr
- D. [P] < [R]
Explanation: Rf = Rr: In a reversible reaction at equilibrium, the rates of the forward and reverse reactions are equal.
Correct answer: Rf = Rr- A. Changing temperature
- B. Adding KCI
- C. Adding NaNO3
- D. Decreasing pressure
Explanation: Adding KCl, which is a common ion with KClO3, would have the effect of increasing the concentration of chloride ions in the solution.
Correct answer: Adding KCI- A. It may or may not have units
- B. It does not depend upon concentrations of reactants and products
- C. It is associated with temperature
- D. It tells us about rate of reaction
Explanation: Option A is correct because Kc can have units or be unitless depending on the reaction's stoichiometry.Option B is correct as Kc is…
Correct answer: It tells us about rate of reaction- A. Low temperature and high-pressure.
- B. Low temperature and low pressure.
- C. High temperature and high pressure.
- D. High temperature and low pressure.
Explanation: Low temperature: Since the reaction is exothermic (ΔH<0), lowering temperature favors the forward reaction (formation of AB₄) to produce…
Correct answer: Low temperature and high-pressure.