Question

count the significant digits in each of these measurements:
measurement number of significant digits
0.004200 j
1.8×10⁻³ ml
-5.0×10⁻³ kj/mol

1. kg

Explanation:

Step1: Identify significant - digit rules for 0.004200 J

Leading zeros are not significant, non - zero digits and trailing zeros after a non - zero digit are significant.

Step2: Determine significant digits for 1.8×10⁻³ mL

In scientific notation, the digits in the coefficient are significant.

Step3: Find significant digits for - 5.0×10⁻³ kJ/mol

The digit 5 and the 0 after it in the coefficient are significant.

Step4: Count significant digits for 84400. kg

The trailing zero after the decimal point is significant, and all non - zero digits are significant.

Answer:

4
2
2
5