Find the relative formula mass of NHCl. (H = 1, C = 12, N = 14, O = 16, Na = 23, Mg = 24, Al = 27, S = 32, Cl = 35.5, K = 39, Ca = 40, Fe = 56, Cu = 63.5, Zn = 65, Ag = 108)
Answer and explanation
Correct answer: D. 53.5
- Step 1: Add the relative atomic masses, taking each atom as many times as its subscript shows: 1 × 14 (N) + 4 × 1 (H) + 1 × 35.5 (Cl).
- Step 2: Total .
Answer
53.5.
Why not the others: 50.5: the subscripts are ignored. 69.5: an extra oxygen atom is counted.
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