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 650 of 686
- A. mol3dm-6
- B. moldm-3
- C. mol-3dm6
- D. No unit
Explanation: A, B and C are incorrect since the given units aren't correct according to the equationD is correct since In equation both sides moles are…
Correct answer: No unit- A. N2 + 3H2--------> 2NH3
- B. SO2 + 2O2--------> 2SO3
- C. CO + H2O ----------> CO2 + H2
- D. 2NO2 + O2---------> 2NO3
Explanation: There are equal moles of reactants and products therefore Kc will have no units as they get cancelled out.
Correct answer: CO + H2O ----------> CO2 + H2- A. H2S2O7
- B. HSO4-
- C. SO3
- D. S
Explanation: In the contact process, sulfur dioxide (formed by roasting sulfur in oxygen) is reacted with oxygen to form sulfur trioxide, which is…
Correct answer: H2S2O7- A. Four
- B. Eight
- C. Five
- D. Six
Explanation: A is incorrect as 6 electrons are present around each Na+ in a NaCl structure.B is incorrect as 6 electrons are present around each Na+ in…
Correct answer: Six- A. 6
- B. 2
- C. 4
- D. 8
Explanation: The coordination number is the number of ions that immediately surround an ion of the opposite charge within a crystal lattice.
Correct answer: 612986. Solubility of Ce2(SO4)3.
- A. Increases with temperature
- B. Decreases with temperature
- C. Shows exceptional behavior
- D. Remains constant
Explanation: The solubility of most salts increases with temperature due to increased kinetic energy and greater interaction between solute and solvent…
Correct answer: Decreases with temperature- A. Iodine.
- B. Benzoic acid.
- C. Solvent.
- D. Stationery.
Explanation: Solvent extraction is an equilibrium process controlled by distribution law or partition law.
Correct answer: Solvent.- A. Cl− ions
- B. SO4−2 ions
- C. PO4−3 ions
- D. Cr+3 ions
Explanation: Explanation:The chromyl chloride test is performed to detect chloride ions in the qualitative analysis.
Correct answer: Cl− ions- A. Mass Spectrometry
- B. X-rays
- C. Chromatography
- D. Solvent Extraction
Explanation: A is correct as mass spectrometry is a method to differentiate between different isotopes of an element.B is incorrect as X-ray cant be…
Correct answer: Mass Spectrometry- A. R spectroscopy
- B. U.V spectroscopy
- C. Mass Spectrometry
- D. N.M.R
Explanation: Mass Spectrometry (MS) is an analytical technique used to measure the mass-to-charge ratio of ions.
Correct answer: Mass Spectrometry- A. Redox Potential
- B. Cell Potential
- C. Oxidation Potential
- D. None of the above
Explanation: Explanation:The emf produced by the Galvanic cell is known as cell potential, which is the difference in reduction potentials of the two…
Correct answer: Cell Potential- A. pH scale
- B. pOH scale
- C. Hydrogen Scale
- D. pKa scale
Explanation: A is incorrect as pH scale is a tool to measure pH(acidity) of a B is incorrect as pOH scale is a tool to measure pOH(alkalinity) of a…
Correct answer: Hydrogen Scale- A. 2H+(aq) + 2e- → H2(g)
- B. H2(g) → 2H+(aq) + 2e-
- C. 2H+(aq) + 2e- → 2H(g)
- D. 2H2- → 2H(g) + 2e-
Explanation: The Standard Hydrogen Electrode (SHE) serves as a benchmark for measuring standard electrode potentials, with a potential of 0 V.
Correct answer: H2(g) → 2H+(aq) + 2e-- A. 20.414 dm3
- B. 22.414 dm3
- C. 22.414 cm3
- D. 23.414 dm3
Explanation: A is incorrect as the given volume is not correct under standard conditions.B is correct as the given volume (22.4 dm3) is correct under…
Correct answer: 22.414 dm3- A. 22.41 dm3
- B. 44.82 dm3
- C. 64.82 dm3
- D. 2.241 dm3
Explanation: To find the volume of a gas, we use the formula: Moles = Volume of gas / 22.
Correct answer: 22.41 dm3- A. N2
- B. H2
- C. O2
- D. Number of molecules are equal
Explanation: The number of molecules is given by the formula:Number of molceules = moles x avogadros constantSince all of the given elements have the…
Correct answer: Number of molecules are equal- A. Acetic Acid
- B. Oxalic Acid
- C. Benzoic Acid
- D. Citric Acid
Explanation: Explanation:Benzoic acid has a high melting point (122°C) and a low vapor pressure, which allows it to sublime at room temperature and…
Correct answer: Benzoic Acid- A. Ammonium sulphate
- B. Sodium chloride
- C. Benzoic acid
- D. Lead carbonate
Explanation: A is incorrect as ammonium sulphate is purified through centrifuging.B is incorrect as sodium chloride is purified by crystallization.C is…
Correct answer: Benzoic acid- A. 60%
- B. 58%
- C. 90%
- D. 50%
Explanation: The above question states that 1-bromopropane i.e CH3-CH2-CH2-Br has a molar mass of 123g is being prepared from 10g of 1-propanol i.e…
Correct answer: 58%13000. A spontaneous process is:
- A. Unidirectional and irreversible
- B. Irreversible and a real process
- C. Unidirectional and a real process
- D. All of the above
Explanation: A is incorrect because spontaneous process is also real processB is incorrect because spontaneous process is also unidirectionalC is…
Correct answer: All of the above