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 15 of 45
- A. Manganese
- B. Tin
- C. Calcium
- D. Carbon
Explanation: Calcium has six stable isotopes: 40, 42, 43, 44, 46, 48Manganese has four stable isotopes: 52, 53, 54, 55Tin has ten isotopes: 112, 114…
Correct answer: Calcium- A. Electrons present in 2g of H
- B. Atoms in 24g of Mg
- C. Atoms in 1g of He
- D. Molecules in 35.5g of Chlorine
Explanation: Avogadro's Number (NA) is the number of atoms, molecules, ions, or anything in one mole of the respective substance.
Correct answer: Atoms in 24g of Mg- A. The number of electrons
- B. The number of neutrons
- C. The number of protons
- D. The number of neutrons and protons
Explanation: The mass number of an atom is defined as the sum of protons and neutrons that are present inside the nucleus of an atom.
Correct answer: The number of neutrons and protons- A. Oxygen
- B. Natural gas
- C. Air
- D. There is no limiting reactant
Explanation: The limiting reactant is the substance that gets completely consumed first, stopping the reaction from continuing.
Correct answer: Natural gas- A. Mole of a substance
- B. Weight of substance
- C. Mass of substance
- D. Molar mass of substance
Explanation: The molar mass of a substance is the mass of 1 mole of that substance, expressed in grams per mole (g/mol).It can be calculated from the…
Correct answer: Molar mass of substance- A. 6.2 x 10^22
- B. 6.22 x 10^22
- C. 6.02 x 10^23
- D. 6.5 x 10^22
Explanation: Answer: C One mole contains an Avogadro's number of particles i.e. 6.02x1023
Correct answer: 6.02 x 10^23- A. Atomic Spectroscopy
- B. Ionic Spectroscopy
- C. Mass Spectroscopy
- D. Mass Spectrometry
Explanation: Atomic spectroscopy is a technique used to study the interaction of electromagnetic radiation with atoms.There is no such thing as "ionic…
Correct answer: Mass Spectrometry- A. Reactant
- B. Products
- C. Both A & B
- D. None of these
Explanation: he limiting reactant controls the amount of products formed in a chemical reaction.
Correct answer: Products- A. 25 NA
- B. 1.1 NA
- C. 1.34 x 10^24
- D. 0.5 NA
Explanation: To find the total number of neutrons in 5g of H2O, we start by calculating the number of moles of water:1.
Correct answer: 1.34 x 10^24- A. Atoms
- B. Molecules
- C. Gas
- D. Solid
Explanation: The ion that is produced when a molecule loses or gains one or more electrons is called a molecular ion, e.g., CH4+, CO+, or N2+.
Correct answer: Gas- A. C3H6O3
- B. C4H4O2
- C. C8H8O4
- D. C6H6O3
Explanation: The molecular mass of the empirical formula is 2(12.1) + 2(1) + 16 = 42.2Now, we need to find 'n' Experimental molecular weight = 165…
Correct answer: C8H8O4- A. 8g of oxygen
- B. 16g of oxygen
- C. 32g of oxygen
- D. 24g of oxygen
Explanation: 27 g of Al = 1 mole of AlWhen balancing the equation: 4Al + 3O2 → 2Al2O3Look at the mole ratioAl : O24 : 31 : 3/44 moles of Al gives 3…
Correct answer: 24g of oxygen- A. Hyperon
- B. Neutrino
- C. Anti-neutrino
- D. All of these options are correct
Explanation: All of them are involved in the composition of atoms. It is a fact.
Correct answer: All of these options are correct- A. 33%
- B. 40%
- C. 53.3%
- D. 6.67%
Explanation: The mass percent of the carbon in a 1.5g sample of glucose is approximately 40%.
Correct answer: 40%- A. Mass
- B. Volume
- C. Moles
- D. All of these
Explanation: Option D is correct as with the "mass" of a substance and the balanced equation of a reaction with that substance, we can calculate the…
Correct answer: All of these- A. 5
- B. 49
- C. 48
- D. 44
Explanation: Option CAtomic mass of H2SO4= 1×2+32+16× 4 = 98Atomic number of H2SO4= 2+16+32 = 50Formula:- number of neutrons = Atomic mass - Atomic…
Correct answer: 48- A. Electrons
- B. Protons
- C. Positrons
- D. Neutrons
Explanation: Isotopes are the atoms of the same element having different numbers of neutrons.
Correct answer: Neutrons- A. Operational losses
- B. Reaction reversibility
- C. Side reaction
- D. All of these
Explanation: Option D is correct since all three of these reasons are responsible for the actual yield being less than the theoretical yield.
Correct answer: All of these- A. Atoms
- B. Particles
- C. Molecules
- D. None of these
Explanation: Option A Different type of gases are madeup of different number of atoms such as argon is made uo of single atom or carbon-dioxide is made…
Correct answer: Particles- A. Rate of reaction
- B. Physical states of reactants and products.
- C. Conditions
- D. All
Explanation: Chemical equations involve the elements involved in a reaction, the number of molecules of the elements, the state symbols.
Correct answer: All