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Which one of the following statements is NOT correct?

Options

  1. AHalf mole of nitrogen gas is measured 11.2 litre at STP
  2. B17 gram of ammonia gas contains 6.022 10²³ molecules at STP
  3. C22.4 litre of CO₂ gas at STP contains 44 gram of molecules
  4. D4 gram of hydrogen gas contains 6.022 10²³ molecules

Correct answer

D. 4 gram of hydrogen gas contains 6.022 10²³ molecules

Step-by-step solution

At STP, 1 mole of any ideal gas occupies 22.4 litres. Half mole of nitrogen gas occupies 1 2 22.4 = 11.2 litres. This statement is correct. Molar mass of ammonia ( NH₃ ) is 17 g/mol. 17 g of ammonia corresponds to 1 mole, which contains 6.022 10²³ molecules. This statement is correct. 22.4 litres of CO₂ gas at STP corresponds to 1 mole. The molar mass of CO₂ is 44 g/mol, so it weighs 44 grams. This statement is correct. Molar mass of hydrogen gas ( H₂ ) is 2 g/mol. 4 grams of hydrogen gas corresponds to 4 2 = 2 mol

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