Chemistry: Scientific Notation and Significant Figures

PRACTICE AND EXAMPLE QUESTIONS

0.00456

3 significant figures (Leading zeros are not counted).

123.450

5 significant figures (All non-zero digits and trailing zeros in the decimal count).

100

1 significant figure (Trailing zeros in a whole number without a decimal point don’t count).

100.0

4 significant figures (Trailing zeros in a decimal count).

0.00780

3 significant figures (Leading zeros are not counted, but the zero in the decimal counts as significant).

5000

1 significant figure (Without a decimal point, trailing zeros do not count).

5000.

4 significant figures (The decimal indicates that all zeros are significant).

0.00010200

5 significant figures (Leading zeros are not counted, but the trailing zeros count).

6.022 × 10²³

4 significant figures (Scientific notation signifies the significant figures in the coefficient).

7.890 × 10⁴

4 significant figures (The significant figures are determined by the decimal form in the coefficient).

0.04560

4 significant figures (Leading zeros are not counted but trailing zeros count).

2.00 × 10⁴

3 significant figures (Trailing zeros in a decimal count as significant).

3000.1

4 significant figures (All digits, including the decimal, count).

123456

6 significant figures (All non-zero digits are significant).

0.000100

5 significant figures (Leading zeros do not count, but the non-zero digits and trailing zeros in decimal count).

9.99 × 10⁻³

3 significant figures (The coefficient in scientific notation shows significant digits).

0.003045

4 significant figures (Leading zeros not counted, all others are significant).

800

1 significant figure (Without a decimal point, trailing zeros don’t count).

800.

3 significant figures (Decimal indicates all zeros are significant).

0.00400

3 significant figures (Leading zeros don't count, but trailing zeros in decimal count).

6.02 × 10²

3 significant figures (Determined by the coefficient).

1.0001

5 significant figures (All digits count).

1.5

2 significant figures (Both digits are significant).

0.070

2 significant figures (Leading zeros do not count).

2500.0

5 significant figures (Decimal point shows all digits are significant).

3.00 × 10³

3 significant figures (The zeros here are significant due to the decimal).

5000.00

6 significant figures (All digits count as significant due to the decimal).

4.50 × 10⁶

3 significant figures (All digits in the coefficient are significant).

39000

2 significant figures (Without a decimal, trailing zeros do not count).

39000.0

6 significant figures (Decimal shows all zeros count).

0.0042

2 significant figures (Leading zeros do not count).

0.05030

4 significant figures (Leading zeros do not count, trailing zeros count).

1.2340 × 10²

5 significant figures (All displayed digits in scientific notation count).

200.00

5 significant figures (All digits, including zeros after the decimal point, count).

0.00670

3 significant figures (Leading zeros do not count, but trailing zeros in decimal do).