Free Fundamental Concepts of Chemistry MCQs with Answers
894 Fundamental Concepts of Chemistry MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Mole calculations connect mass, number of particles and Avogadro's number, while balanced equations provide the mole ratios used in stoichiometry. Questions cover limiting and excess reactants, theoretical yield and percentage yield, including identifying which reactant is consumed first and comparing the actual product with the maximum possible product.
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Read the Fundamental Concepts of Chemistry notesFree MDCAT chapter notes with key terms894 questions · page 43 of 45
- A. Shape
- B. Size
- C. Molecularity
- D. Atomicity
Explanation: OPTION A: The shape of a molecule determines its geometry. OPTION B: The size of a molecule tells us how small or big it is.
Correct answer: Atomicity- A. 24 NA
- B. 2 NA
- C. 20 NA
- D. 1 NA
Explanation: The atomic number of magnesium is 12. Mg+2 means it has lost 2 electrons. Therefore, In the Mg+2 ion, there are 12-2 = 10 electrons. No.
Correct answer: 20 NA- A. 0.1, 0.2
- B. 0.1, 0.3
- C. 0.2, 0.4
- D. 0.2, 0.1
Explanation: d) 0.2 moles of hydrogen ions (H+) and 0.1 mole of sulfate ions (SO4^2-):Using the same calculation as above, we get:Moles of H+ ions ≈…
Correct answer: 0.2, 0.1- A. 8g of oxygen
- B. 16g of oxygen
- C. 32g of oxygen
- D. 24g of oxygen
Explanation: Option D is the right answerSolution number of moles of Al = given mass/molar mass=27/27= 1 moleThe balance equation for such reaction…
Correct answer: 24g of oxygen- A. Mass
- B. Volume
- C. Moles
- D. All of these options are correct
Explanation: If we are given the mass of a substance, we can calculate the mass, volume, and moles of the other substance with the help of a balanced…
Correct answer: All of these options are correct- A. 1
- B. 2
- C. 3
- D. 4
Explanation: Correct option is B. A molecule of water has two bonds so 1 mole of water will contain 2 mole of bonds.
Correct answer: 2- A. Qualitative
- B. Quantitative
- C. Both A & B
- D. Extensive
Explanation: Both qualitative and quantitative analysis were used in the 17th century to study the composition of pure substances.
Correct answer: Quantitative- A. One million
- B. Two million
- C. One billion
- D. Two billion
Explanation: 'Fullstops' contain millions of atoms, substantiating how small atoms are, to an extent where millions can fit in a small dot, placed…
Correct answer: Two million- A. Rate constant
- B. Enthalpy
- C. Temperature
- D. Yield
Explanation: The rate of reaction can be determined by a number of methods, including physical and chemical methods.
Correct answer: Yield- A. Percentage
- B. Actual
- C. Theoretical
- D. Combination of all of these
Explanation: The actual yield is obtained from the reaction. Theoretical yield is calculated from a balanced chemical equation.
Correct answer: Percentage- A. Percentage
- B. Actual
- C. Theoretical
- D. All of these options are correct
Explanation: The efficiency of a chemical reaction is determined by the percentage yield, that is the ratio of theoretical yield to actual yield…
Correct answer: Percentage- A. 10 moles.
- B. 8 moles.
- C. 6 moles.
- D. 4 moles.
Explanation: Balance chemical equation2H2 + O2 -> 2H20Now we will compare the moles of H2 and O2 with water from the balanced chemical equation.H2…
Correct answer: 10 moles.- A. Is mostly a cheaper substance and taken in larger quantity
- B. Is consumed earlier and controls the amount of product formed in a chemical reaction
- C. Gives greatest number of moles of products
- D. Is left behind after the completion of reaction
Explanation: Explanation: A limiting reactant is the one which is consumed earlier and controls the amount of product formed in a chemical reaction.
Correct answer: Is consumed earlier and controls the amount of product formed in a chemical reaction- A. Mass-mass relationship
- B. Mass-mole relationship
- C. Mole-volume relationship
- D. Mass-volume relationship
Explanation: A is incorrect as mass-mass relationship involves converting the mass of a reactant to moles of reactant, then using mole ratios to…
Correct answer: Mass-volume relationship- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: D is correct as Avogadros law states - Equal volume of all ideal gases at equal temperature contain equal number of moles
Correct answer: Option D- A. 6.67 x 10^-14
- B. 1.5 x 10^-14
- C. 6.67 x 10^14
- D. 1.5 x 10^14
Explanation: As we have to distribute 5 rupee coins to 100 people so,100/5 =20 coinsNow multiply these coins by the total population alive in…
Correct answer: 6.67 x 10^-14- A. 4g of O2
- B. 4.5g of H2O
- C. 4g of Cl2
- D. 1 moles of NaCl
Explanation: First, we need to calculate the number of moles of CO2 in 11g of CO2 So, 44g of CO2 is 1 mole, then 11g of CO2 is how many moles?
Correct answer: 4.5g of H2O- A. CH2O
- B. C4H12O2
- C. C2H6O
- D. CH4O
Explanation: Convert g CO2 to g C.Convert g H2O to g H.g O = total g - g C - g Hg C = g CO2 x (C/CO2) = 1.039 x 12.01/44.01 = approx 0.2833g g H = g…
Correct answer: C2H6O- A. An atom of C - 12
- B. 1/12th of a carbon
- C. 1/12th of H
- D. 1 atom of all the elements
Explanation: The atomic mass unit (amu) is a unit of mass used to express the mass of atomic and subatomic particles.
Correct answer: 1/12th of a carbon- A. Mass of an element
- B. Empirical formula mass
- C. Molar mass of an element
- D. Formula mass
Explanation: Since molar mass is constant for a given element, increasing the mass increases the number of moles proportionally.
Correct answer: Mass of an element