Consider the following statements and choose the correct option: (1) The mass of 15 moles of H2 is 30 g. (2) The number of moles present in 128 g of O2 is 4.

Answer: A. Both the statements are correct.

The molar mass of H2 is 2 g/mol. Therefore, the mass of 15 moles of H2 = 15 x 2 = 30 g, so statement 1 is correct. The molar mass of O2 is 32 g/mol. The number of moles in 128 g of O2 = 128 / 32 = 4 moles. Hence, statement 2 is also correct. Therefore, both statements are correct.

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