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MDCAT
Chemistry
2021

Chemistry · Stoichiometry

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Question
According to Avogadro's law, 0.899g of 1dm3 H2 and 1.4384g of 1dm3 O2 have _____________number of molecules. 
Options
  • A
    Same
  • B
    Different
  • C
    H2 has more
  • D
    O2 has more
Explanation

According to Avogadro's law, 0.899g of 1dm³ H₂ and 1.4384g of 1 dm³ of O₂ have the same number of molecules. Avogadro's law states that "equal volume of all gases beneath comparable situations of temperature and pressure have an equal number of molecules in it."

According to Avogadro's law, equal volumes of different gases at the same temperature and pressure contain an equal number of molecules. Avogadro's number, denoted by "NA ," is approximately 6.022 x 10²³ molecules per mole.First, we need to find the number of moles for each gas:1. For hydrogen (H₂):Given mass of H₂ = 0.899 gMolar mass of H₂ = 2 g/mol (1 g/mol for each hydrogen atom)Number of moles of H₂ = Mass / Molar mass = 0.899 g / 2 g/mol ≈ 0.4495 mol2. For oxygen (O₂):Given mass of O₂ = 1.4384 gMolar mass of O₂ = 32 g/mol (16 g/mol for each oxygen atom)Number of moles of O₂ = Mass / Molar mass = 1.4384 g / 32 g/mol ≈ 0.04495 molNow, we need to find the number of molecules for each gas:Number of molecules = Number of moles x Avogadro's number (Nₐ)1. For hydrogen (H₂):Number of molecules of H₂ = 0.4495 mol x 6.022 x 10²³ molecules/mol ≈ 2.706 x 10²³ molecules2. For oxygen (O₂):Number of molecules of O₂ = 0.04495 mol x 6.022 x 10²³ molecules/mol ≈ 2.707 x 10²² moleculesSo, approximately 0.899g of hydrogen gas (H₂) contains about 2.706 x 10²³ molecules, and 1.4384g of oxygen gas (O₂) contains about 2.707 x 10²² molecules.

According to Avogadro's law, equal volumes of different gases at the same temperature and pressure contain an equal number of molecules. Avogadro's number, denoted by "NA ," is approximately 6.022 x 10²³ molecules per mole.

According to Avogadro's law, equal volumes of different gases at the same temperature and pressure contain an equal number of molecules. Avogadro's number, denoted by "NA ," is approximately 6.022 x 10²³ molecules per mole.

According to Avogadro's law, equal volumes of different gases at the same temperature and pressure contain an equal number of molecules. Avogadro's number, denoted by "NA ," is approximately 6.022 x 10²³ molecules per mole.

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Tagged under Chemistry · Stoichiometry · 2021