1st Year Chemistry Chapter 01 Basic Concept MCQs Quiz Test

If you are looking MCQs for 1st year Chapter One "Basic Concept" MCQs Question Answers with solutions you are here on right website. On this Page you will learn Chapter One objective type solved Questions with solutions. All of these chapter wise first Year Chemistry question answers are helpful for upcoming exams and tests preparations. These MCQs are also helpful for entry tests.

1st Year Chemistry MCQs Quiz Test

You Will Learn In this Chapter:

• Atom/Molecule/Ion
• Relative Atomic Mass
• Isotopes
• Mass Spectrometry
• Empirical Formula by Combustion Analysis
• Empirical and Molecular Formula
• Concept of Mole
• Avogadro’s Number
• Mole Volume
• Stoichiometry
• Limiting Reactant

First Year Chemistry Chapter One Basic Concepts MCQs With Answers

Q.1: The largest number of moles are present in:?

1. 3.6g H₂O
2. 2.8g CO
3. 4.8g C₂H₅OH
4. 5.4g N₂O₅

A

Q.2: The stoichiometric calculations for a chemical reaction results in:?

1. Actual yield
2. Theoretical yield
3. Percentage yield
4. Selectivity

C

Q.3: Which of the following not has equal number of atoms as that in 6g Molybdenum (A_r : 96)?

1. 3 g O₃
2. 4 g SO₂
3. 4 g Ca
4. 5 g SO₃

C

Q.4: 1 gram molecule refers to:?

1. Amount in grams equivalent to 1 mole of an atom
2. Amount in grams equivalent to 1 mole of a molecule
3. Amount in grams equivalent to 1 mole of a molecule or a compound
4. Amount in grams of an ionic compound

B

Q.5: Number of H⁺ ions when 0.1 mole of sulfuric acid is completely ionized in water:?

1. 4×6.022 x 10²³
2. 2×6.002 x 10²³
3. 1 x 6.022 x 10²³
4. None of these

D

Q.6: 1 gram formula refers to:?

1. Amount in grams equivalent to 1 mole of an atom
2. Amount in grams equivalent to 1 mole of a covalent compound
3. Amount in grams equivalent to 1 mole of an ionic compound
4. Amount in grams equivalent to 1 mole of an ion

C

Q.7: How many electrons have to be removed to ionize 1.0 x 10^-6 mol of Ne atoms to Ne⁺ ions in a neon advertising tube??

1. 6.02 x 10²³ / 1.0 x 10^-6
2. 1.0 x 10^-6 x 6.02 x 10²³ / 20.2
3. 1.0 x 10^-6 x 6.02 x 10²³
4. 1.0 x 10^-6 x 6.02 x 10²³ / 9.65 x 10^-1

C

Q.8: One mole of SO₂ contains:?

1. 6.002 x 10²³ atoms of Oxygen
2. 6.002 x 10²³ atoms of Sulphur
3. 18.1 x 10²³ molecules of SO₂
4. 4 g atoms of SO₂

B

Q.9: Mg reacts with HCl as per the following reactions:

Mg_(s) + 2HCl_(aq) → MgCl_2(aq) + H_2(g)
Given that; Mg = 21g and HCl = 21g, the excess reactant is;?

1. Mg
2. HCl
3. Both are present in an equal stoichiometric amount
4. None of these

A

Q.10: 5604 cm³ of H₂ gas at STP contains of hydrogen:?

1. 6.02 x 10²³
2. 2.6 x 10²³
3. 3.01 x 10²³
4. 1.50 x 10²³

B

Q.11: Number of moles present in 0.6 grams of silica is (Atomic mass Si = 28, O = 16)??

1. 0.01 mole
2. 0.064 mole
3. 0.044 mole
4. 0.054 mole

A

Q.12: Gram atoms of hydrogen in 5.5g H_2:?

1. 5.50
2. 2.25
3. 5.45
4. 2.20

A

Q.13: Mass in grams of 10 moles of aspartame (C₁₄H₁₈N₂O₅):?

1. 29400g
2. 2940g
3. 2850g
4. 2800g

B

Q.14: % of the nitrogen in urea (NH₂CONH₂):?

1. 82.35%
2. 35%
3. 46.6%
4. 55.56%

C

Q.15: One mole of potassium chlorate is thermally decomposed and excess of aluminum is burnt in the gaseous mixture. How many moles of aluminum oxide is formed? Respective equations are given as:

2KClO₃ → KCl + 3O₂4Al + 3O₂ → 2Al₂O₃?

1. 1
2. 2
3. 1.5
4. 3

A

Q.16: In a mass spectrometer, increasing the magnetic field strength with constant electric field results in??

1. Increased radius ‘r’
2. Increased ionization
3. No effect
4. Increased ionization

C

Q.17: In a mass spectrometer, increasing the electric field with constant magnetic field results in:?

1. Increased radius ‘r’
2. Increased ionization
3. Decreased radius ‘r’
4. None of the above

A

Q.18: When 0.5 moles of Al₂(SO₄)₃ are dissolved in water, the total number of particles produced??

1. 1.2 x 10²³
2. 3.0 x 10²³
3. 1.5 x 10²⁴
4. 2.5 x 10²³

C

Q.19: A smuggler was caught by Airport police and 24 g of diamond was recovered from him. How many atoms of carbon he was carrying??

1. 6 x 10²³
2. 1.8 x 10²⁴
3. 1.2 x 10²⁴
4. 2.4 x 10²⁴

C

Q.20: Which of the following contains 1 mole of the stated particle??

1. Chlorine molecules in 35.5 g of chlorine gas
2. Electrons in 1g of hydrogen gas
3. Hydrogen ions in 1dm³ of 1 mol dm^-3 aqueous sulphuric acid
4. Oxygen atoms in 22.4 dm³ of oxygen gas at STP

B

Q.21: During combustion analysis, which one is used for absorbing carbon dioxide??

1. 50% KOH solution
2. Mg (ClO₄)₂
3. Silica gel and Mg (ClO₄)₂
4. Silica gel

A

Q.22: Which one is a monoisotopic element??

1. Cl
2. H
3. F
4. Cd

C

Q.23: Molecular ions are produced in the mass spectrometer. Which type of molecular ions is more abundant??

1. Negatively charged
2. Positively charged
3. H⁺ ions
4. Equal positive and negative ions

B

Q.24: The height of the peak in mass spectrum shows:?

1. Number of isotopes
2. Mass Number
3. Relative abundance
4. Number of protons

C

Q.25: The separation of different isotopes in the mass spectrometer is done on the basis of:?

1. Different amounts of positive change on each ion
2. Different m/e
3. Different e/m value
4. Velocities of the ions

C

Q.26: Which of the following compounds has the highest % age of oxygen by weight??

1. CH₃ – OH
2. C₂H₅ – OH
3. HCCOOH
4. H₂O

D

Q.27: A compound contains 50% sulphur and 50% oxygen by mass. The empirical formula of the compound is:?

1. S₂O₃
2. SO₃
3. SO₂
4. SO

C

Q.28: Equal volumes of CO and N₂ are taken in identical conditions, The correct relationship between masses of two gases is??

1. CO < N₂
2. N < CO₃
3. CO = N₂
4. All of these

C

Q.29: The technique that is not used to separate isotopes is:?

1. Thermal diffusion
2. Ultracentrifuge
3. Distillation
4. Extraction

D

Q.30: Combustion analysis is performed for the determination of:?

1. The molar mass of the compound
2. The structural formula of the substance
3. The empirical formula of the compound
4. Mass of halogens present in an organic compound

C