Q44E - Chemistry (OpenStax)

Question

Express each of the following numbers in scientific notation with correct significant figures:

(a) 711.0

(b) 0.239 

(c) 90743

(d) 134.2

(e) 0.05499

(f) 10000.0

(g) 0.000000738592

Step-by-Step Solution

Answer

(a) 7.110 × 10²

(b)  2.39 × 10^-1

(c)  9.0743 × 10⁴

(d)  1.342 × 10²

(e)  5.499 × 10^-2

(f)  1.00000× 10^-4

(g) 7.38592 × 10^-7

Step 1: Significant and non-significant figures

• All non-zero digits are significant.
• Captive zero/zeros present in between non-zero digits are significant.
• Trailing zero, i.e., zeros present to the right of the decimal, are significant.
• Leading zeros, zeros which come before non-zero digits and the decimal, are not significant and only denote the place of the decimal.

Step 2: Express numbers in scientific notation

Number of significant figures in numbers given above-

(a) The scientific notation of 711.0 is 7.110 × 10² with 4 significant figures.

(b)  The scientific notation of 0.239 is 2.39 × 10^-1, with 3 significant figures.

(c)  The scientific notation of 90743 is 9.0743 × 10^{4 ,} with 5 significant figures.

(d)  The scientific notation of 134.2 is 1.342 × 10^2, with 4 significant figures.

(e)  The scientific notation of 0.05499 is 5.499 × 10^-2, with 4 significant figures.

(f)  The scientific notation of 10000 is 1.00000 × 10^-4, with 6 significant figures.

(g)   The scientific notation of 0.000000738592 is 7.38592 × 10^-7, with 6 significant figures.