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Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.
Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.
  • a)
    Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
  • b)
    Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
  • c)
    Assertion (A) is true but reason (R) is false.
  • d)
    Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Verified Answer
Direction : In the following questions, a statement of assertion (A) ...
Avogadro’s law states that under the same conditions of temperature and pressure, equal volumes of different gases contain an equal number of molecules. This empirical relation can be derived from the kinetic theory of gases under the assumption of a perfect (ideal) gas. The law is approximately valid for real gases at sufficiently low pressures and high temperatures. At STP, all gas have same volume for 1 mol of gas and that volume is always equal to the 22.4 L.
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Most Upvoted Answer
Direction : In the following questions, a statement of assertion (A) ...
Assertion: One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.

Reason: One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.

Explanation:
- The assertion states that one mole of molecules has a mass equal to the gram molecular mass. This is true because one mole of any substance contains Avogadro’s number of particles, which is approximately 6.022 x 10^23. The gram molecular mass is the molar mass of the substance expressed in grams. Therefore, one mole of molecules has a mass equal to the gram molecular mass.
- The assertion also states that one mole of molecules contains Avogadro’s number of molecules or has a volume of 22.4 L at STP (standard temperature and pressure) if the substance is a gas. This is also true because at STP, one mole of any ideal gas occupies a volume of 22.4 L. This is known as molar volume.
- The reason states that one mole of an ionic compound has a mass equal to the gram formula unit mass and contains Avogadro’s number of formula units. This is also true because one mole of any ionic compound contains Avogadro’s number of formula units, which is equal to the number of ions present in the compound. The gram formula unit mass is the molar mass of the compound expressed in grams.
- Therefore, both the assertion and the reason are true, but the reason is not the correct explanation of the assertion. The reason provides additional information about the mass and number of formula units in one mole of an ionic compound, but it does not explain why one mole of molecules has a mass equal to the gram molecular mass or why one mole of molecules has a volume of 22.4 L at STP if the substance is a gas.
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Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer?
Question Description
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? for Class 9 2024 is part of Class 9 preparation. The Question and answers have been prepared according to the Class 9 exam syllabus. Information about Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 9 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer?.
Solutions for Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 9. Download more important topics, notes, lectures and mock test series for Class 9 Exam by signing up for free.
Here you can find the meaning of Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer?, a detailed solution for Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : One mole of molecules has mass equal to gram molecular mass and contains Avogadro’s number of molecules or has a volume of 22.4 L at STP if the substance is a gas.Reason : One mole of an ionic compound has mass equal to gram formula unit mass and contains Avogadro’s number of formula units.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice Class 9 tests.
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