Discovering Design With Chemistry
A bowl has a volume of 1.1 L. What is its volume in cubic cm?
1,100 cm cubed 1.1 L / 1 x 1 mL/ 0.001 L = 1,100 mL
Density
a measure of how tightly-packed the matter in a substance is
Convert the following measurements into decimal notation: a. 1.2 x 10 to the -2 km b. 7.82 x 10 to the 7 mL c. 9.1 x 10 to the - 8 kg d. 8.912 x 10 to the 6
a. 0.012 km b. 78,200,000 mL c. 0.000000091 kg d. 8,912,000 m
Convert the following measures into scientific notation with 4 significant figures each: a. 0.0001214 kg b. 34,500 m c. 123,500,000 mg d. 0.01010 km
a. 1.214 x 10 to the -4 kg b. 3.45 x 10 to the 4 m c. 1.235 x 10 to the 8 mg d. 1.010 x 10 to the -2 km
Is ice more or less dense than water?
less dense
You are measuring the volume of an object using a scale that is marked off with lines that represent mL on each. To what level of precision should you report your measurement?
one mL
An object has a mass of 123.4 kg, which is the same as 8.456 slugs. Which measures more mass: one kg or one slug?
one slug
Weight
a measure of how strongly gravity pulls on an object
The volume of a soccer ball is 6,080 mL. How many kL is that?
0.00608 kL. 6,080 mL/ 1 x 0.001 L/ 1 mL= 6.08 L 6.08 L/ 1 x 1 kg/ 1,000 L= 0.00608 kL
A US dime has a diameter of 17.9 mm. What is the diameter in m?
0.0179 m. 17.9 mm / 1 x 0.001 m/ 1mm
A sample of liquid has a volume of 143. 6 L. What is the volume in m cubed?
0.1436 m cubed. 143.6 L / 1 x 1 mL/ 0.001 L = 143,600 mL 143,600 cm cubed / 1 x (0.01m / 1 cm) cubed = 143,600cm cubed/1 x 0.000001 m cubed/ 1 cm cubed = 0.1436 m cubed
An object has a length of 15.0 inches. What is its length in meters? (2.54 cm = 1 inch)
0.381 m. 15.0 in/ 1 x 2.54 cm/ 1 in = 38.1 cm 38.1 cm/1 x 0.01 m/ 1 cm = 0.381 m
A soup can has a mass of 490 grams. What is its mass in kg?
0.49 kg. 490 g/1 x 1 kg/ 1000 g
Aluminum has a density of 2.70 g/cm3. What is the volume of an aluminum block that has a mass of 55. 67 kg?
20,600 mL. 55.67 kg/ 1 x 1,000 g/ 1 kg = 55,670 g d=m/v v·d= m/v·v v·d= m v·d·1/d= m·1/d v= m/d v=55,670 g/2.70 g/mg= 20,600 mL
What is the correct answer to the equation 21. 0234 g - 12 g?
9 g.
significant figure
A digit in a measurement that contributes to the measurement's precision
Mass
A measure of how much matter exists in an object
Unit
A quantity that describes the measurement being made
Matter
Anything that has mass and takes up space
What are the three base metric units used to measure length, mass, and time
Meters, grams, and seconds
When a figure is significant, does that mean it is mathematically important?
NO!
The true measurement of a floor is such: Length-- 4.6 m, Width-- 3.2 m. A carpet layer says the floor measures 14.72. What two things are wrong with this measure?
No units and incorrect number of sig figs.
A box has a volume of 1.01 m to the third. Two students measure it. The first says the volume is 1 cubed, while the second says the volume is 1.23 m cubed. Assuming they are recording the correct number of significant figures for the measuring device used, which student used the more precise device? Which student had the more correct answer?
Second had more precise device, first had more correct answer.
Two students are measuring the mass off an object. One says it measures 4.56 g, while the other says 4.58 g. However, both students receive 100% credit. HOW??
There is always uncertainty in the last significant figure.
You are snooping in a scientist's lab notebook and see a measurement of 14.5 mL. What was the scientist measuring: Length, Mass, Volume, or Time?
Volume.
A sample of what looks like silver has a mass of 1.7 kg and a volume of 0.164 l. Is it really silver? (Silver's density is 10.49 g/mL)
YES. 1.7 kg/1 x 1,000 g/ 1 kg = 1,700 g 0.164 L/ 1 x 1 mL/ 0.001 L = 164 mL d = m/v. 1,700/ 164 mL= 1.0 x 10 g/mg
How many significant figures are in the following measurements? a. 1.06x10 to the fourth mL b. 12,000 cm c. 0.0340 kg d. 1.0x10 in
a: 3 b: 2 c: 3 d: 2
