Question

2. There are 8 confirmed planets in our solar system. The number of significant figures in this number is 1. True or False? Explain.

3 Do the following calculations, reporting the correct number of significant figures in your answer.

a) 6.53x10^3g/12.8mL

b) 5.621mL+ 22.4mL+5mL

c) 3.3mm x 23.4mm x 1.769mm

d) (965.43 x 3.911)+ 9413.4136

4. Preform the following conversions, reporting the correct number of significant figures in your answers.

a) 1.976 x 10^-3 g to micro g

b) 1.25 x 10^8 cL to ML

c) 3.77 x 10^4 mm^3 to nm^3

d) 8.65 g/cm^3 to kg/m^3

Answer 1

Significant figure rule :

If any number that has no any decimal place and that is unit place that has 1 significant figure so the statement is true.

3).

In multiplication and dividing we use answer with minimum number of significant number that has to the number in the calculation

In addition and subtraction we use digits after decimal places so the number in calculation that has minimum number of digits after decimal are given to the answer.

Lets use this information do the following calculations.

1. 6.53x10^3g/12.8mL = 510. g/mL
2. 5.621mL+ 22.4mL+5mL = 33
3. 3.3mm x 23.4mm x 1.769mm = 1.4 x 10² mm³
4. (965.43 x 3.911)+ 9413.4136 = 13189.

Conversions

G to microgram

1.976 x 10^-3 g to micro g

1 g = 1.0 x 10³ mg

Lets use this as a conversion factor.

Mass in g = 1.976 x 10^-3 g x ( 1.0 X 10³ mg /1 g ) = 2.0 mg

Centi to M L

            1 c L = 1.0 x 10^-8 ML

Conversion from

=1.25 E 8 cL x ( 1 ML^-8 / 1.0 cL )

= 1.25 ML

c)

3.77 x 10^4 mm^3 to nm^3

= 3.77 x 10^4 mm^3 x ( 10^18 nm / 1 mm)

= 3.77 x 10^22 nm^3

d)\

= (8.65 x g / cm^3) x ( 1 cm^3 / 1 x 10^-6 m^3 ) x ( 1 kg / 1000 g )

= 8.65 x 10² kg / m^3