Question 10 • LA-Chemistry A
In (NH₄)₂SO₄, the subscripts give 2 nitrogen atoms, 8 hydrogen atoms, 1 sulfur atom, and 4 oxygen atoms. Using rounded atomic masses, the total is 2(14.01) + 8(1.01) + 32.07 + 4(16.00) = 132.17 amu. So the formula mass is 132.17 amu, choice D.
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