Matter & Changes
What is matter?
Anything that has mass and volume (takes up space)
A measurement is considered accurate if it is close to what?
The actual/true value
Convert 0 0C to Kelvin.
273 K (or 273.15 K)
Convert 3.5 km to meters.
3,500 m
Write 4,500 in scientific notation.
4.5 x 103
Name 3 common states of matter.
Solid, Liquid, and Gas
A student repeatedly measures an object's mass and gets: 5.21g, 5.22g, 5.21g, 5.22g
These measurements are very close to one another. This demonstrates what?
High Precision
Convert 68 0F to C.
C= 5/9 (F-32)
20 0C
Convert 6 ft to centimeters.
2.54 cm = 1 inch
182.88 cm
ft -> in -> cm
Write 0.00072 in scientific notation.
7.2 x 10-4
A block of ice melts into liquid water. Is this a Chemical or Physical change? Explain why.
Physical change. The substance remains water and only its state changes. Reversible.
True or False: A measurement can be very precise without being accurate.
Explain why.
True. Measurements can be very close to each other while still being far from the actual/true, accepted value.
Convert 25 0C to F.
F = 9/5 C +32
77 0F
Convert 125 lb to grams.
2.205 lb = 1 kg
56,699 g
lb -> kg -> g
Write 4.43 x 108 in standard notation.
443,000,000
A piece of wood is burned and turned into ash, smoke, and gases. Is this a Chemical or Physical Change? Explain why.
Chemical change. New substances are produced and the composition changes. Not reversible.
How many significant figures are in each measurement?
A. 0.00450 B. 830 C. 8.0003 D. 750. E. 0.0400
A. 3 B. 2 C. 5 D. 3 E. 3
Convert 95 0C to K.
368 K
A container has a mass of 55.7 g. When filled with maple syrup, the mass rises to 235.8 g. The density of the syrup is 0.88 g/cm3. What is the volume of the syrup.
D = M/V
V = 204.66 cm3
Mass: 235.8 g - 55.7 g = 180.1 g
180.1 g divided by 0.88 g/cm3
Write 1.086 x 10-8 in standard notation.
0.00000001086
For each situation, identify whether it is a Chemical or Physical Change.
1. Water freezes 2. Silver tarnishes
3. A piece of paper is torn 4. Sugar dissolves in water
5. Gasoline burns
1. Physical 2. Chemical 3. Physical 4. Physical
5. Chemical
Underline the zeros in each measurement that are significant AND write the total number of SF.
A. 0.78 B. 0.078 C. 0.0780 D. 7.08005204
E. 7.08 F. 780 G. 7800. H. 0.09030
A. no zeros, 2 sf B. no zeros, 2 sf
C. last zero, 3 sf D. all four zeros, 9 sf
E. one zero, 3 sf F. no zeros, 2 sf
G. two zeros, 4 sf H. last two zeros, 4 sf
A chemistry experiment is performed at 95 0F. Convert the temperature to BOTH 0C and K.
C = 5/9 (F-32)
35 0C and 308 K
Convert 150 miles per hour to meters per second.
1 mi = 5,280 ft
2.53 cm = 1 in
67.056 m/sec
150 mi/1 hr, 5280 ft/1 mi, 12 in/1 ft, 2.54 cm/1 in, 1 m/100 cm, 1 hr/60 min, 1 min/60 sec
Which number is larger?
A. 3.5 x 105 B. 8.2 x 104
How many times larger?
3.5 x 105 4.27 times greater
350,000/82,000 = 4.27