Download App

Atoms and Molecules Science - Atoms and Molecules

Rajasthan Board (RBSE) - STD 9 - Science (Rajasthan - English Medium). 610 questions in this chapter.

Question types

Atoms and Molecules question types

610 questions across 8 question groups — pick any mix to generate a Science paper with step-by-step answer keys.

610
Questions
8
Question groups
5
Question types
Sample Questions

Atoms and Molecules questions

One sample from each question group in this chapter. Select any group above to see the full set with answer keys.

Q 1M.C.Q. [1 M]1 Mark
A solution of copper oxide was prepared by heating, igniting and precipitation. Which of the following method will give higher ratio of copper oxide:
View full solution →
Q 2M.C.Q. [1 M]1 Mark
A student wants to have $3.011 \times 10^{23}$ atoms each of magnesium and carbon elements. For this purpose, he will have to weigh:
View full solution →
Q 4M.C.Q. [1 M]1 Mark
The scientist who proposed the first letter (or first letter and another letter) of the Latin or English name of an element as its symbol, was:
View full solution →
Q 6Assertion (A) & Reason (B) MCQ1 Mark
In the following questions, a statement of assertion $(A)$ is followed by a statement of reason $(R).$
Mark the correct choice as:
  1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
  2. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
  3. If Assertion is true but Reason is false.
  4. If Assertion is false and Reason is true.
  5. If both Assertion and Reason are false.
Assertion: Atomicity of $O_3$ is $3.$
Reason: $1$ mole of an element contains $6.023 \times 10^{23}$ atoms.
View full solution →
Q 7Assertion (A) & Reason (B) MCQ1 Mark
In the following questions, a statement of assertion $(A)$ is followed by a statement of reason $(R).$
Mark the correct choice as:
  1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
  2. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
  3. If Assertion is true but Reason is false.
  4. If Assertion is false and Reason is true.
  5. If both Assertion and Reason are false.
Assertion: $SI$ unit of atomic mass and molecular mass is $kg.$
Reason: It is equal to the mass of $6.023 \times 10^{23}$ atoms.
View full solution →
Q 8Assertion (A) & Reason (B) MCQ1 Mark
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: $23g$ of $Na$ contains $6.022 \times 10^{23}$ sodium atoms.
Reason: $23g$ of $Na$ contains $1$ atom of $Na.$
  • A
    Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
  • B
    The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.
  • ✓
    Assertion is true but the Reason is false
  • D
    The statement of the Assertion is false but the Reason is true.

Answer: C.

View full solution →
Q 9Assertion (A) & Reason (B) MCQ1 Mark
In the following questions, a statement of assertion $(A)$ is followed by a statement of reason $(R).$
Mark the correct choice as:
  1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
  2. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
  3. If Assertion is true but Reason is false.
  4. If Assertion is false and Reason is true.
  5. If both Assertion and Reason are false.
Assertion: When $10g$ of $Caco_3$ is decomposed$, 5.6g$ of residue is left and $4.4g$ of $CO_2$ escapes.
Reason: Law of conservation of mass is followed.
View full solution →
Q 10Assertion (A) & Reason (B) MCQ1 Mark
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
  1. Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
  2. The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.
  3. Assertion is true but the Reason is false
  4. The statement of the Assertion is false but the Reason is true.
Assertion: The formula of aluminium sulphate is $Al_2(SO_4)_3.$
Reason: The valency of Al is $3$ and charge on $SO_4^{2-}.$
View full solution →
Q 12true or false1 Mark
State whether the following statements are true or false:
A chloride ion has negative charge because it has more electrons than a neutral atom.
View full solution →
Q 13true or false1 Mark
State whether the following statements are true or false:
A sodium ion has positive charge because it has more protons than a neutral atom.
View full solution →
Q 17Fill in the blank1 Mark
Fill in the following blanks with suitable words:
In a chemical reaction, the sum of the masses of the reactants and the products remains unchanged. This is called _________.
View full solution →
Q 30Que-Ans (Each of 3 Mark )3 Marks
When 5g of calcium is burnt in 2g of oxygen, then 7g of calcium oxide is produced. What mass of calcium oxide will be produced when 5g of calcium is burnt in 20g of oxygen? Which law of chemical combination will govern your answer?
View full solution →
Q 37Que-Ans (Each of 4 Mark )4 Marks
Raunak took $5$ moles of carbon atoms in a container and Krish also took 5 moles of sodium atoms in another container of same weight.
$a.$ Whose container is heavier?
$b.$ Whose container has more number of atoms?
View full solution →
Q 38Que-Ans (Each of 4 Mark )4 Marks
In an experiment, $4.90g$ of copper oxide was obtained form $3.92g$ of copper. In another experiment, $4.55g$ of copper oxide gave, on reduction, $3.64g$ of copper. Show with the help of calculations that these figures verify the law of constant proportions.
View full solution →
Q 39Que-Ans (Each of 4 Mark )4 Marks
Write the formulae for the following and calculate the molecular mass for each one of them.
$a.$ Caustic potash
$b.$ Baking powder
$c.$ Lime stone
$d.$ Caustic soda
$e.$ Ethanol
$f.$ Common salt
View full solution →
Browse all question groups ↑

Generate a Atoms and Molecules paper free

Pick question groups from the list above, set marks and difficulty, and export a branded PDF with step-by-step answer keys. First 3 chapters free — no signup.

Download App
Generate Paper FreeAll Science chapters