Lesson: Chapter 7 — Quantification of Elements and Compounds

7.2. Relative molecular mass 7 of 10 Reset answers

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Question 7

What is the formula mass of sodium chloride (NaCl)? (A_r: Na = 23, Cl = 35.5)

A 12.5 B 58.5 C 23 D 35.5

The right answer is the one marked above.

58.5. NaCl = 23 + 35.5 = 58.5.

12.5 comes from subtracting instead of adding. A formula mass is always obtained by adding.

Answer the question to continue.