Description
Ch. 2 Chemistry and MeasurementsDon't forget about the age old question of What revolution was characterized by the shift from agrarian to industrial economy?
Standard measurements = metric system
Measurement
Metric
SI
length
Meter (m)
meter(m) kilometers(km)
volume
Liter (L)
Cubic meter (m3)
mass
Gram (g)
Kilogram (kg)
temperature
Degree celsius (oC)
Kelvin (k)
time
Scond (s)
Second (s)
We also discuss several other topics like 1.0075^12
1m = 100 cm 1m = 1.09 yd
1m = 39.4 in 2.54 cm = 1 in.If you want to learn more check out What forms around ions when water is dissolving salts?
We also discuss several other topics like Describe the coronary circulation.
Don't forget about the age old question of What significant event led to the The Tenure of Office Act (1867)?
Volume is the space occupied by a substance. The si unit of volume is m3, however, the metric system, volume is based on the liter, which is a tad larger than a quart.
Mass of an object is a measure of the quantity of material. Kilogram (kg) is used for larger masses. gram (g) is used for smaller masses.If you want to learn more check out Is Bernard William persuasive?
Temperature tells us how hot or cold something is. Celsius (oC) & Kelvin (K)
Water freezes at 37° F or 0°C
The Kelvin scale for temperature begins at the lowest possible temp, O K
Time is measured in units, minutes, hours, days, etc we will use seconds (s).
Measured numbers are the numbers obtained when you measure a quantity of something (Significant Figures) all the digits, including estimated digit Sig Fig are used
Measured number
Number of Significant Figure
50
2
45
2
48 x 102
2
3000
1
3000.
↖Makes a difference
4
Exact Numbers Not measured & do not have a limited number of significant figures, Not used to find the number of sig fig in a calculated answer.
Numbers obtained by counting 8 cookies
Definitions that compare 2 units 6 eggs
Def, of the same measuring system 1qt = 4 cups
1kg = 1000g
Rules for rounding
3.1457 g ↓
3.146 g ↓
3.15 g ↓
Multiplication and Division
24.66 cm x 0.35 cm = 8.631 (calculator display)
= 8.6 cm2 (2 sig fig)
17.04 2.0 = 8.5 cm
Addition and Subtraction
The final answer is written so that it has the same number of decimal places as the measurement with the fewest decimal places.
2.012 65.09
61.09 - 3.0
+ 3.0 62.09
66.102 62.1 correct answer
66.1 correct answer
82.409 mg
+ 22.0 mg
104.409 mg
104.4 mg
Prefixes and Equalities
Kilo = always means 1000
1000 gram = 1 kilogram
1000 seconds = 1 kilosecond
1000 liters = 1 kiloliter
1000 m = 1 km
milli = “one thousandth of”
Prefixes that increase the size of the unit
Peta P 10-1
Tera T 10-2
Giga G
Mega M 106
Kilo K 103