# CHM 50- Class activity

```CHM 50
Chapter 1 – Class activity
Name …………..
1. Express the following numbers as scientific notation
A. 0.000 0015 m = …………….
B. 72 00000 g = ………………..
2.
Express the following numbers as decimals
a)
1.52 x 10-4 = ………………..
b)
1.6001 x 104 = …………………………
c)
1 x 10-4 = ……………………..
d)
7.78 x 105= ………………………..
3.
Round off or add zeros to the following calculated answers to give three significant figures.
A. 824.75 cm ………………….
B. 0.112486g………………………….
C. 8.2 L …………………………
4.
State the number of significant figures in each of the following measurements.
5.
A. 0.030 m
(………..)
B.
4.050 L (……………)
C. 0.0008 g
(………..)
D.
2.80 m (………….)
For each calculation, round off the calculated answer to give a final answer with the correct number of
significant figures.
A. 2.19 x 4.2
=
C. 12.56 + 4.6 - 3.624 =
6.
B. E. (0.0105 x 0.060) + 84.0567 =
D.
102 – 40.6 &divide; 10.45 =
Indicate the unit that matches the description.
a)
A mass that is 1000 times greater than 1 gram
c) A unit of time that is 1/1000 of a second.
b) A length that is 1/100 of 1 meter.
d) A volume that is 100 times smaller than liter
7.
Without changing the significant figures of the original values, re-write the number using the (closet) correct
prefix for the following measurements
a.
0.000065g = …………………..
c.
0.425 ms = ……………………
b)
6365920 m = ………………..
1.
Complete the table below
Problem
1.54 cm to in
Given quantity
1845 kg to lb
2.70 g/cm3 to kg L
Needed quantity
Possible equalities
Set-up
2. A bucket contains 4.65 L of water. Write the setup for the problem and calculate the gallons of water in quart.
3. An injured person loses .50 pints of blood. How many milliliters of blood would that be? Identify the given
and needed units given in this problem.
4. If your pace on a treadmill is 65 meters per minute, how many minutes will it take for you to walk a distance of
7500 feet?
5.
How many lb of sugar are in 120 g of candy if the candy is 25.0 % (by mass) sugar? (hint: write the
expression of 25.0% to obtain an equality)
6. The density of octane, a component of gasoline, is 0.702 g/mL. What is the mass, in kg, of 875 mL of octane?
7. A group of students collected 125 empty aluminum cans to take to the recycling center. If 21 cans make 1.0 lb
aluminum, how many liters of aluminum (D=2.70 g/cm3) are obtained from the cans?
8. An infant acetaminophen suspension contains 80 mg/0.80 mL suspension. The recommended dose is 15
mg/kg body weight. How many mL of this suspension should be given to an infant weighing 14 lb?
9. An ebony carving has a mass of 275 g. If ebony has a specific gravity of 1.33, what is the volume (ml) of the
carving?
```