NeetVictoryQuestion 1: Laws of Chemical Combination
The mass of one mole of carbon-12 atoms is exactly:
- A 1 g
- B 12 u
- C 12 g
- D 6.022 g
Answer: C. 12 g
Why: This is how the mole and the atomic mass unit are linked.
NEET Chemistry: Some Basic Concepts of Chemistry. Chapter-wise Practice Questions and Test
Some Basic Concepts of Chemistry is a Class 11 Chemistry chapter that carries about 2.3% of the Chemistry questions in NEET. Practise it with 39 questions covering 2 topics, each with an explanation.
Practise Some Basic Concepts of Chemistry
Open in the appSets of 15 questions that adapt to your level, with an explanation for every answer.
Topics covered in Some Basic Concepts of Chemistry
- Laws of Chemical Combination (8 questions)
- Mole Concept and Stoichiometry (31 questions)
How often Some Basic Concepts of Chemistry has come up in NEET
Across the 13 previous year papers, Some Basic Concepts of Chemistry had 22 questions, about 1.7 a year. The most in one paper was 4, in AIPMT 2014.
| Paper | Questions from this chapter |
|---|---|
| NEET 2026 | 1 |
| NEET 2025 | 2 |
| NEET 2024 | 3 |
| NEET 2023 | 1 |
| NEET 2022 | 1 |
| NEET 2021 | 1 |
| NEET 2020 | 1 |
| NEET 2019 | 1 |
| NEET 2018 | 2 |
| NEET 2017 | 0 |
| NEET 2016 | 1 |
| Re-AIPMT 2015 | 4 |
| AIPMT 2014 | 4 |
Sample questions on Some Basic Concepts of Chemistry with answers
8 questions from the practice bank, spread across the chapter's topics. The full set is in the app.
Question 2: Mole Concept and Stoichiometry
The mass of a single water molecule is about:
- A 1.8 × 10⁻²³ g
- B 3 × 10⁻²³ g
- C 3 × 10⁻²³ kg
- D 6 × 10⁻²³ g
Answer: B. 3 × 10⁻²³ g
Why: 18 g/6.022 × 10²³ ≈ 2.99 × 10⁻²³ g.
Question 3: Laws of Chemical Combination
The law of multiple proportions states that when two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other are:
- A always equal
- B in a ratio of small whole numbers
- C random and unrelated
- D always in a 1:1 ratio
Answer: B. in a ratio of small whole numbers
Why: The law of multiple proportions (Dalton) states that when two elements form more than one compound, the masses of one element combining with a fixed mass of the other are in a ratio of small whole numbers.
Question 4: Mole Concept and Stoichiometry
The number of atoms in 0.5 mol of oxygen gas (O₂) is:
- A 1.2 × 10²⁴
- B 3.011 × 10²³
- C 6.022 × 10²²
- D 6.022 × 10²³
Answer: D. 6.022 × 10²³
Why: 0.5 mol of O₂ is 0.5 × 6.022 × 10²³ molecules, and each has two atoms.
Question 5: Laws of Chemical Combination
One atomic mass unit (1 u) is defined as:
- A the mass of one proton exactly
- B the mass of one hydrogen atom
- C 1/12 of the mass of one carbon-12 atom
- D 1/16 of the mass of an oxygen molecule
Answer: C. 1/12 of the mass of one carbon-12 atom
Why: The unified atomic mass unit is defined using carbon-12, whose mass is exactly 12 u.
Question 6: Mole Concept and Stoichiometry
The mass of 3.011 × 10²³ molecules of CO₂ (molar mass 44 g/mol) is:
- A 88 g
- B 11 g
- C 44 g
- D 22 g
Answer: D. 22 g
Why: 3.011 × 10²³ is half a mole, so the mass is 22 g.
Question 7: Laws of Chemical Combination
The law of definite proportions, given by Proust, states that:
- A the elements in a compound combine in a ratio that depends on how it was prepared
- B the total mass of reactants equals the total mass of products
- C equal volumes of gases at the same conditions contain equal numbers of molecules
- D a pure compound always contains the same elements combined in the same fixed ratio by mass
Answer: D. a pure compound always contains the same elements combined in the same fixed ratio by mass
Why: Whatever the source or method of preparation, a given compound has a fixed composition by mass.
Question 8: Mole Concept and Stoichiometry
100 mL of a 2 M solution is diluted to 500 mL by adding water. The new molarity is:
- A 0.2 M
- B 0.4 M
- C 1 M
- D 10 M
Answer: B. 0.4 M
Why: M₁V₁ = M₂V₂ gives M₂ = 2 × 100/500.
Practise all of Some Basic Concepts of Chemistry
Open in the appFrequently asked questions
How many questions come from Some Basic Concepts of Chemistry in NEET?
Some Basic Concepts of Chemistry carries about 2.3% of the Chemistry questions in NEET. Across the 13 previous year papers on NeetVictory it appeared 22 times, about 1.7 questions a year.
Which class is Some Basic Concepts of Chemistry from?
Some Basic Concepts of Chemistry is a Class 11 Chemistry chapter in the NCERT syllabus.
Where can I practise Some Basic Concepts of Chemistry questions for NEET?
NeetVictory has 39 practice questions on Some Basic Concepts of Chemistry, each with an explanation, in sets of 15 that adapt to your level. This page shows a free sample.