1. FACTOR LABEL
HOMEWORK

2. 1.
1.55 x 106 nm = km
This is just a metric conversion ---- always 2 steps.
Start with what
you’re given:
One step to the BASE unit, meters:
One step to the desired unit, kilometers:
1.55 x 106 nm
1x10-9 m 1 km x 1 nm
1x103 m
1.55x10-6 km

3. 2.
Tg = g
This is just a metric conversion ---- always 2 steps.
Start with what
you’re given:
One step to the BASE unit, grams:
One step to the desired unit, micrograms:
1x1012 g 1 g Tg x 1 Tg
1x10-6 g
9.3x1011 g

4. 3. x 8.5 x 10-20 Ml = ml 8.5 x10-20 Ml 1x106 l 1 ml 1 Ml 1x10-3 l
This is just a metric conversion ---- always 2 steps.
Start with what
you’re given:
One step to the BASE unit, liters:
One step to the desired unit, milliliters:
8.5 x Ml
1x106 l 1 ml x 1 Ml
1x10-3 l
Or you could use this for last fraction 
1000 ml
1 l
8.5x10-11 ml

5. 4. x x 8 gallons = liters 4 8 gal qt .94 l 1 gal 1 qt 30.08 liters
Gallons is an English unit and liters is a metric unit - determine what Metric-English conversion will work (from box at top of homework)
Start with what
you’re given: 4
8 gal qt
.94 l x x 1
gal 1 qt
1 sig fig
30.08 liters
30 liters

6. Keep converting to bigger units of time until you get to years:5.
5.75 x 1015 s = years
Start with what
you’re given:
Keep converting to bigger units of time until you get to years: 1
min 1 hr 1
days 1 yr
5.75 x1015s x x x x 60 s 60
min 24 hr
365
days
1.82x108 yr

7. This has 2 dimensions. Convert ml to qt and min to hr6.
500 ml/min = qt/hr
This has 2 dimensions. Convert ml to qt and min to hr
Start with what
you’re given:
ml is on top
Min on bottom
500 ml
min
1x10-3 l 1 qt 60
min x x x 1
.94 l hr 1 ml
31.9 qt/hr
1 sig fig
30 qt/hr

8. 7. x x 9 in2 = cm2 2.54 9 in2 cm 2.54 cm 1 in 1 in 58.1 cm2 60 cm2
Start with what
you’re given:
But in won’t cancel in2 , so multiply by “1” again!
9 in2
2.54 cm in cm
2.54 1 x x 1 in
58.1 cm2
We only started with 1 sig fig
60 cm2

9. 8. x x x x 55 miles/hr = m/s 55 mi hr 1.61 1x103 m 1 hr 1 min km 1 mi
Remember --- get a good start  miles on TOP & hours on BOTTOM
Start with what
you’re given:
I’ll get miles to meters first:
Then I’ll get hr to seconds:
55 mi hr
1.61
1x103 m 1 hr 1
min km x x x x 1 mi 1 km 60
min 60 s
24.6 m/s
We only started with 2 sig figs
25 m/s