Question

Determine the number of significant figures in the following measurements: (a) 0.0009, (b) 15,450.0, (c) 6×103, (d) 87.990, and (e) 30.42.

a) (a) 1 (b) 6 (c) 1 (d) 5 (e) 4
b) (a) 1 (b) 6 (c) 1 (d) 5 (e) 4
c) (a) 1 (b) 6 (c) 1 (d) 5 (e) 4

Answer 1

Significant figures are determined by several rules. Measurements 0.0009, 15,450.0, 6x10³, 87.990, and 30.42 have 1, 6, 1, 5, and 4 significant figures respectively, applying the relevant rules for leading, trailing, and sandwiched zeros, as well as scientific notation.

Step-by-step explanation:

To determine the number of significant figures in the following measurements, we should apply the rules of significant figures:

• Non-zero digits are always significant.
• Any zeros between significant digits are significant.
• Leading zeros (zeros before non-zero numbers) are not significant.
• Trailing zeros in a number containing a decimal point are significant.
• In a number with a scientific notation, only the digits in the coefficient are considered for significant figures.

The number of significant figures in each measurement is:

1. 0.0009 has 1 significant figure. The zeros are leading and do not count.
2. 15,450.0 has 6 significant figures. The zeros are between non-zero digits and at the end after a decimal, so they are significant.
3. 6x10³ has 1 significant figure. The coefficient (6) is the only significant digit.
4. 87.990 has 5 significant figures. The trailing zeros are significant since they are after the decimal point.
5. 30.42 has 4 significant figures. All the non-zero digits and the zeros between them are significant.