# Unit 1 ```Math Unit
Welcome to Chemistry!
1. Scientific Notation
• Exponential notation from
math class
• Example: 12,500,000
• Example: 0.000368
• Example: 2.3 x 10-2
• Example: 5.6 x 103
2. Density
• 1 mL = 1 cm3
• Example: An unknown liquid has a
mass of 42 g and occupies a volume
of 102 cm3. What is its density? Could
this unknown be a salt water solution
that has a density of 0.40 g/mL?
• What is the mass of a
substance that occupies
250 mL and has a density of
0.698 g/cm3?
3. Metric Base Units
•
•
•
•
gram (g) – mass
liter (l) – volume
meter (m) – length
second (s) – time
4. Metric Prefixes
•
•
•
•
•
•
•
•
mega (M) 1Mg = 1,000,000 g = 1 x 106 g
kilo (k)  1 kg = 1000 g
deci (d)  1 g = 10 dg
centi (c)  1 g = 100 cg
milli (m)  1g = 1000 mg
micro (u)  1 g = 1 x 106 ug
nano (n)  1 g = 1 x 109 ng
pico (p)  1 g = 1 x 1012 pg
5. Dimensional Analysis
• Brittany wants to know her
height in meters. She knows
that her height is 1.86 km.
• During a lab, Becca poured
4.2 x 102 mL of hydrochloric
acid into a beaker. How many
liters is this?
• Owen needed to obtain
5.3 x 10-1 g of sodium chloride
for his experiment. How many
nanograms did he need?
• A chemist needs
5.6 x 1014 pg of iron. How
many kilograms is this?
• A student runs 0.26 Mm.
How many centimeters did
this student run?
3
cm
• Ben needs 420
of water.
How many microliters does
he need?
• 2.54 cm = 1 inch
• How many meters are in
1 yard?
• How many feet are in
1.2 x 105 mm?
6. Velocity calculations
• Garrett drives his truck 114
km/hr down Cavalier Drive.
How fast is he driving in meters
per second?
• Shamyra’s speed in the 400m
run was 14 km/hr. What would
her speed be in inches per
second?
• Mrs. Fulks was late to work this morning
and got a speeding ticket for driving
92 mph down King William Rd. How
fast was she going in kilometers per
minute?
7. Mass conversions
• How many grams of apples did
I buy at Food Lion if I
purchased 2.75 lbs?
(Hint: 1 pound = 454 g)
8. Significant Figures
• All nonzero digits ARE significant
• All “trapped” zeros are significant
• Trailing zeros in the decimal
portion ONLY are significant
• Any number before the “x 10” is
significant
• 56
• 301
• 1000
• 0.00500
• 5.6 x 10-20
9. Sig Fig Calculations
• 2.0014 + 5.36 + 1.2597423 =
• (3.642)(1.02)(8.9) =
10. Accuracy
• Getting the right (or accepted)
value
11. Precision
• Getting the same data (value)
over and over even if it is NOT
the correct value
12. Percent Error
• In a lab experiment, you find the
density of aluminum to be 3.14
g/mL. If the accepted value for
the density of aluminum is 2.70
g/mL, what is your percent error?
```