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 18 of 45
- A. 0.86 L
- B. 2.24 L
- C. 4.06 L
- D. 1.12 L
Explanation: Following is the solution to this question:
Correct answer: 1.12 L- A. 10 mL of H2
- B. 5 mL of H2
- C. 10 mL of O2
- D. 5 mL of O2
Explanation: Step 1:Volume of H2 = 30 ml volume of O2 = 20 ml reaction between H2 and O2 to form water is as follows:H2+12O2⟶H2O 30mL 15 mL reactedStep…
Correct answer: 5 mL of O2- A. Two
- B. Six
- C. Four
- D. Nine
Explanation: Two isotopes are for each Cl and BrFour isotopes are for SSix isotopes are each for Pd and CaNine isotopes are for Cd
Correct answer: Six- A. 280
- B. 40
- C. 300
- D. 154
Explanation: 280 different isotopes occur in nature including 40 radioactive isotopes as well.300 unstable radioactive isotopes produced through…
Correct answer: 300345. The total types of fundamental nuclear sub-atomic particles are there in teh nucleus of an atom?
- A. More than 100
- B. 2
- C. 3
- D. Equal to 100
Explanation: In the nucleus of an atom protons and neutrons are present.
Correct answer: 2- A. A ZX
- B. AXZ
- C. ZAX
- D. ZXA
Explanation: AZX, A is the atomic mass and Z is the atomic number.
Correct answer: A ZX- A. 0.01 mole
- B. 0.064 mole
- C. 0.044 mole
- D. 0.054 mole
Explanation: To calculate the number of moles in 0.6 grams of silica, we first need to calculate the molar mass of silica.
Correct answer: 0.01 mole- A. 6.02 x 10^23/32
- B. 32 g
- C. 0.32 g
- D. 32 / 6.02 x 10^23
Explanation: The molecular mass of a molecule expressed in grams is called gram molecule or mole so 32 g is the molar mass of O2 .
Correct answer: 32 / 6.02 x 10^23349. 3 x 10^-21 moles of an amino acid having a molecular mass of 200 g mol-1, would have molecules?
- A. 200
- B. 1800
- C. 300
- D. 36000
Explanation: N=n x NAN=3 x 10-21 x6.02 x 1023N=1800Hence, option b is correct.
Correct answer: 1800- A. 25 g of iodine (I2)
- B. 25 moles of oxygen (O)
- C. 25 moles of water (H2O)
- D. 25 g of nitrogen gas (N2)
Explanation: Mass of I2 = 25 gmass of O atoms= 25 x 16= 400 gmass of H2O = 25 x 18= 450 gmass of N2 gas= 25 gSo, H20 has the maximum mass.
Correct answer: 25 moles of water (H2O)- A. CH3OH
- B. C2H5OH
- C. HCOOH
- D. H2O
Explanation: Molecular Formula: H2OMolecular Weight: (2 * 1.01) + 16.00 = 18.02 g/molOxygen Weight: 16.00 g/molPercentage of Oxygen by Weight: (16.00 /…
Correct answer: H2O- A. 2.24 dm3
- B. 22.4 dm3
- C. 112 cm3
- D. 1.12 dm3
Explanation: No. Of moles (n) = mass/ M.mass=4.4/44 = 0.1 mole Volume = n x 22.414 dm3 = 0.1 x 22.414=2.24 dm3
Correct answer: 2.24 dm3- A. Chlorine molecules in 35.5 g of chlorine gas
- B. Hydrogen ions in 1 dm3 of 1 mol dm-3 aqueous sulphuric acid
- C. Electrons in 1 g of hydrogen gas
- D. Oxygen atoms in 22.4 dm3 of oxygen gas at STP
Explanation: The correct answer is Option C. 1 g of hydrogen gas (H2) is approximately 0.5 moles, and each H2 molecule has 2 electrons, providing 1…
Correct answer: Electrons in 1 g of hydrogen gas- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Option D is correct.The explanation is given in image.
Correct answer: Option D- A. 10
- B. 5
- C. 5.5 NA
- D. 5 NA
Explanation: Option D is correct.The explanation is given in image.
Correct answer: 5 NA- A. 64g
- B. 100g
- C. 32g
- D. 71g
Explanation: The relative atomic mass of oxygen is 16 amu, which means that one mole of oxygen atoms has a mass of 16 grams.
Correct answer: 64g- A. H20
- B. C6H6
- C. H2O2
- D. NaCI
Explanation: Ionic compounds do not have molecule, rather than that they have a formula unit (empirical formula).
Correct answer: NaCI- A. Mg
- B. HCl
- C. Both are in stoichiometric amounts
- D. MgCl2
Explanation: If equal masses of reactants are given then the reactant whose larger molar mass is used in balance chemical equation is limiting reactant…
Correct answer: Mg- A. 4
- B. 2
- C. 8
- D. 16
Explanation: Moles of 'H' atom in given volume of gas22.414 dm3 (I mole) of methane gascontain 4 moles of H-atoms11.207 dm3 (0.5) of methane gas…
Correct answer: 2- A. Side reaction
- B. Reversible nature
- C. Mechanical loss
- D. All of these
Explanation: Due to side reaction, reversible reaction and mechanical loss, actual yield is less than theoretical yield.
Correct answer: All of these