Transcript PRE-AP CHEMISTRY DIMENSIONAL ANALYSIS WORKSHEET #2

PRE-AP CHEMISTRY
DIMENSIONAL ANALYSIS
WORKSHEET #2
1. In the country of Ferdovia, the Ferds thrive on
potatoes. The average Ferd earns 142 thrubs (the local
currency of Ferdovia) per week and spends
approximately 8.0% of his yearly income on potatoes. If
potatoes cost 2 thrubs per pound, how many pounds of
potatoes does the average Ferd consume per year?
1 yr 52wks 142 thrubs 8 pot. thrubs 1 lb pot.
1 yr 1 wk
100 thrubs 2 pot. thrubs
= 3.0 x 102 pounds of potatoes per year
142 thrubs 8 pot. thrubs 1lb pot.
52 wks
1 wk
100 thrubs 2 pot thrubs 1 yr
= 3.0 x 102 pounds of potatoes per year
2. The volume of seawater on earth is estimated to be 3.3
x 108 mi3. Assuming that seawater is 3.5% sodium
chloride, by mass, and that the density of seawater is 1.03
g/cm3, what is the approximate mass of sodium chloride
dissolved in the seawater on earth, expressed in kg? 1
mile = 5280 ft, 1 meter = 39.37 inches
3.3 x 108 mi3 (5280)3ft3 (12)3in3 1 m3
(100)3cm3 1.03g 3.5gNaCl 1 kg NaCl
1 mi3
1 ft3
(39.37)3in3 1 m3
1cm3 100g H2O 1000g NaCl
= 5.0
x 1019kg NaCl
3. A slow jogger runs a mile in 13 min.
Calculate the speed in meters per second.
( 1 mi = 1.609 km; 1 in = 2.54 cm)
1 mi. 1.609km 1000m 1 min
13 min. 1 mi. 1 km 60s
= 2.1
m/s
4. In a city with heavy automobile traffic such as Los
Angeles or New York, it was estimated that about 9.0 tons
of lead from exhaust was deposited on or near the
highway each day before gasoline became “unleaded”.
What is this amount in pounds per month? ( 1 ton =
exactly 2000 lb; 1 month = 31 days)
9.0 tons 2000 lb 31 days
1 day
1 ton 1 month
= 5.6 x 105 lb/month
1 month 31 days 9.0tons 2000 lbs
1 month 1 day 1 ton
= 5.6 x 105 lb/month
5.The density of diamond is 3.51 g/mL. What
is the volume of the Hope diamond if it has a
mass of 44.0 carats? ( 1 carat = 0.200g)
44.0 carats 0.200g 1 mL
1 carat 3.51g
= 2.51
mL
6. Ipecac syrup is used to induce vomiting in people
who have swallowed a poison. The syrup contains
7.0g of ipecac per 100.0 mL, and the recommended
dosage is 1 tablespoon, or 15 mL. Calculate the
amount of ipecac in the average dose.
15 mL 7.0g ipecac
100.0 mL
= 1.1g ipecac
The use of ipecac is no longer
recommended!
7. The LD50 for a drug is the dose that would be lethal
for 50% of the population. LD50 for sodium cyclamate
in mice is 17.0grams per kilogram of body weight.
Calculate how many cans of diet soda a 70.0 kilogram
human would have to drink to achieve this dose,
assuming each can of diet soda contains 0.096 grams of
sodium cyclamate.
70.0 kg man 17.0g SC 1 can diet soda
1 kg man 0.096 g SC
=12,000 cans!!!!