Unit 2 Test Review

The number of sig figs in 100.00 is _____.

The number of significant figures in 100000000 is _____.

The number of significant figures in 0.000008 is _____.

The number of sig figs in 0.00400 is _____.

Answer explanation

The number 0.00400 has three significant figures: the '4's and the trailing '00' after the decimal point are significant. The leading zeros are not counted as they only indicate the position of the decimal.

The number of significant figures in 9009.00 is _____.

Answer explanation

The number 9009.00 has 6 significant figures. All non-zero digits are significant, and the trailing zeros after the decimal point also count as significant.

The number of sig figs in 4000. is _____.

Answer explanation

The number 4000. has 4 significant figures because the decimal point indicates that the trailing zeros are significant. Therefore, the correct answer is 4.

Round 0.010229 to four sig figs

Round 1009 to three sig figs

Answer explanation

To round 1009 to three significant figures, we look at the first three digits (100). The next digit (9) is 5 or more, so we round up, resulting in 1010. Therefore, the correct answer is 1010.

What is the measurement 1042 Liters rounded to 2 significant figures? 

• 1040 L

• 1.1 x 10³ L

• 1.0 x 10³ L

• 1050 L

Answer explanation

To round 1042 liters to 2 significant figures, we look at the first two digits (10) and the next digit (4). Since 4 is less than 5, we keep it as 1.0 x 10^3 L, which is the correct choice.

What is 98.907 rounded to 1 significant figure?

• 98.9

• 90

• 100

• 98.91

Answer explanation

To round 98.907 to 1 significant figure, we look at the first digit (9) and the next digit (8). Since 8 is 5 or more, we round up, making it 100. Thus, the correct answer is 100.