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 23 of 45
- A. Isotopes have the same electronic configuration because they have the same atomic number.
- B. Isotopes have the same atomic number, affecting their chemical properties.
- C. Isotopes of an element have different mass numbers, influencing their physical properties.
- D. Isotopes of an element have different atomic numbers.
Explanation: The variation of atomic mass in isotopes can influence its physical properties like Density, Melting and boiling point and…
Correct answer: Isotopes of an element have different mass numbers, influencing their physical properties.- A. Number of ions
- B. Empirical formula of organic compounds
- C. Structural formula
- D. Isotope of an element
Explanation: Combustion analysis provides valuable information for determining the empirical formula or molecular formula of an organic compound by…
Correct answer: Empirical formula of organic compounds- A. Chemical change
- B. Physical change
- C. Neither chemical nor physical change
- D. Irreversible change
Explanation: 2 KOH + CO₂ → K₂CO₃ + H₂OIt is a chemical change because it involves breaking and forming new chemical bonds.
Correct answer: Chemical change- A. H2O
- B. H2O2
- C. C6H6
- D. NaCl
Explanation: Correct. It is an ionic compound and ionic compounds don't have Molecular formula but only Empirical formula(formula unit)
Correct answer: NaCl- A. C3H4O4
- B. C2H2O
- C. C2H2O4
- D. C2HO2
Explanation: C : H : O34.6/12 :3.5/1 : 61.5/163 : 4 : 4=> E:F= C3H4O4=>E.F.Mass= (3x12)+(1x4)+(4x16) = 104=> n= Molecular Mass/ E.F.Mass = 104/104 =1=>…
Correct answer: C3H4O4- A. Ionic formula
- B. Structural formula
- C. Empirical formula
- D. Molecular formula
Explanation: The empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound.Ionic formula is the…
Correct answer: Empirical formula- A. Empirical formula
- B. Molecular formula
- C. Ionic formula
- D. Covalent formula
Explanation: The molecular formula provides information about the elements present in the compound and their respective ratios.
Correct answer: Molecular formula- A. C4H6
- B. C6H6O
- C. C2H4
- D. C3H6O
Explanation: X + O2 --> CO2 + H2OMoles of Co2= 88/44= 2Moles of H2O= 36/18= 2So the compound X has 2 moles of C and 4 moles of H(its H2 in H2O, so…
Correct answer: C2H4- A. CH2O
- B. C2H4O2
- C. C6H12O6
- D. C3H6O3
Explanation: Molecular Formula shows actual ratios of atoms present in each molecule, so it has 6 C, 12 H, 6 O, so Molecular formula is C6H12O6.
Correct answer: C6H12O6- A. C6H12O6
- B. C6H6O2
- C. C12H22O11
- D. All
Explanation: Because its atom's ratios cannot be simplified, so E.F and M.F are the same
Correct answer: C12H22O11- A. 80 moles of atoms
- B. 40 moles of hydrogen atoms
- C. 30 moles of electrons
- D. 30 moles of oxygen atoms
Explanation: 2H + O --> H2OH : H2O2 : 1X : 20X=40 moles of hydrogen atom. (Correct)
Correct answer: 40 moles of hydrogen atoms- A. 4
- B. 8
- C. 16
- D. 32
Explanation: H2 + O -> H2O=>O : H2O 1 : 1 X : 0.5 X= 0.5 mol of O atom=> Mole=Mass/Mr Mass=Mole x Mr Mass= 0.5 x 16 Mass= 8 g
Correct answer: 8- A. 2.24 dm3
- B. 112 cm3
- C. 22.4 dm3
- D. 1.12 dm3
Explanation: Moles = Mass / Mr= 4.4 / 48= 0.1● Volume= Mole x 22.4 dm3(in STP)= 0.1 x 22.4= 2.24 dm3
Correct answer: 2.24 dm3- A. 24dm3
- B. 22.4dm3
- C. 80dm3
- D. 40dm3
Explanation: At Standard Temperatureand Pressure, The molar volume of a gas is it's 22.4dm3 (learn it).
Correct answer: 22.4dm3- A. 4
- B. 2
- C. 8
- D. 16
Explanation: Volume= moles x 22.4dm3(in STP)Volume/22.4 = moles11.207/22.4 = 0.5 moles of methane.
Correct answer: 2- A. 22.4dm³
- B. 11.2dm³
- C. 1.12dm³
- D. 1.4dm³
Explanation: At STP, one mole of an ideal gas occupies 22.4 dm³. The molar mass of N2 is 28 g/mol.
Correct answer: 1.12dm³- A. 48g
- B. 10g
- C. 64g
- D. 320g
Explanation: 1 mole of H2SO4 has 32g Sulphur.So 1.5 mole of H2So4 has (1.5 x 32)g Sulphur, that is 48 grams.
Correct answer: 48g- A. 11.2dm³
- B. 22.4dm³
- C. 5.6dm³
- D. None of these
Explanation: Moles = Mass / Mr = 8/32 = 0.25 mol of O2.Volume= Moles x 22.4dm³(at STP) = 0.25 x 22.4 = 5.6dm³
Correct answer: 5.6dm³- A. 0.1
- B. 6
- C. 0.01
- D. 0.6
Explanation: Mr of glucose= (12x6)+12+(16x6) =>180. 1mol of C6H12O6 => 6mol of Carbon 180g of C6H12O6 => 6mol of Carbon 18g of C6H12O6 => xmol of…
Correct answer: 0.6- A. 22.4dm³
- B. 11.2dm³
- C. 44.8dm³
- D. None of the above
Explanation: Volume = Moles x 22.4dm3 = 0.5 x 22.4 = 11.2dm³.
Correct answer: 11.2dm³