Which of the following measurements is expressed with the most significant figures?

• A. 0.00450
• B. 100.0
• C. 12.300
• D. 7.10

Answer: (C)

Verified step by step guidance

1. Understand that significant figures (sig figs) are the digits in a number that carry meaningful information about its precision, including all nonzero digits, any zeros between them, and trailing zeros in the decimal portion.
2. Analyze each number to count its significant figures:
3. For 0.00450, ignore the leading zeros (which are not significant). The digits '4', '5', and the trailing zero after the decimal point are significant, so it has 3 significant figures.
4. For 100.0, the trailing zero after the decimal point is significant, so all four digits (1, 0, 0, and 0) count, giving 4 significant figures.
5. For 12.300, all digits including the trailing zeros after the decimal point are significant, so it has 5 significant figures.
6. For 7.10, the zero after the decimal point is significant, so it has 3 significant figures.
7. Compare the counts: 0.00450 (3 sig figs), 100.0 (4 sig figs), 12.300 (5 sig figs), 7.10 (3 sig figs). The number with the most significant figures is 12.300.