Question

all nonzero numbers are significant. zeros between nonzero numbers are significant. trailing zeros that are only significant if there is a decimal zeros to the left of the first nonzero digits are not significant, they merely indicate the position of the decimal point. (placeholders) are you stuck? check out this video on youtube (see digital copy on google classroom) directions: identify the number of significant figures in each number. 1. 5.432 s = 2. 40.319 g = 3. 1460 cm = 4. 0.1809 s = 5. 2873.0 ml = 6. 0.0000242 mg = 7. 200320 m = 8. 1.09 x 10^7 g = 9. 3.01 x 10^5 cm = 10. 7.90 x 10^4 km =

Explanation:

Step1: Recall significant - figure rules

Non - zero digits are always significant. Zeros between non - zero digits are significant. Trailing zeros are significant if there is a decimal point. Leading zeros (zeros to the left of the first non - zero digit) are not significant.

Step2: Analyze number 1: 5.432 s

All digits are non - zero. So, the number of significant figures is 4.

Step3: Analyze number 2: 40.319 g

Non - zero digits and zero between non - zero digits are significant. So, the number of significant figures is 5.

Step4: Analyze number 3: 1460 cm

There is no decimal point, so the trailing zero is not significant. The number of significant figures is 3.

Step5: Analyze number 4: 0.1809 s

Leading zero is not significant, non - zero digits and zero between non - zero digits are significant. So, the number of significant figures is 4.

Step6: Analyze number 5: 2873.0 ml

Non - zero digits and trailing zero (due to decimal point) are significant. So, the number of significant figures is 5.

Step7: Analyze number 6: 0.0000242 mg

Leading zeros are not significant, non - zero digits are significant. So, the number of significant figures is 3.

Step8: Analyze number 7: 200320 m

Zeros between non - zero digits are significant, but trailing zeros without a decimal point are not significant. So, the number of significant figures is 5.

Step9: Analyze number 8: 1.09×10⁷ g

In scientific notation, all digits in the coefficient (1.09) are significant. So, the number of significant figures is 3.

Step10: Analyze number 9: 3.01×10⁵ cm

In scientific notation, all digits in the coefficient (3.01) are significant. So, the number of significant figures is 3.

Step11: Analyze number 10: 7.90×10⁴ km

In scientific notation, all digits in the coefficient (7.90) are significant. So, the number of significant figures is 3.

Answer:

1. 4
2. 5
3. 3
4. 4
5. 5
6. 3
7. 5
8. 3
9. 3
10. 3