final Flashcards
Mass
All the substances that make up our world
Organic Chemistry
The study of substances that contain the element carbon.
Inorganic Chemistry
The study of all other substances except those that contain carbon.
General Chemistry
The study of the composition, properties, and reactions of matter.
Geochemistry
The study of the chemical composition or ores, soils, and minerals of the surface of earth and other planets.
Biochemistry
The study of the chemical reactions that take place in biological systems.
Physical Chemistry
The study of the physical nature of chemical systems including energy changes.
Chemical
A substance that always has the same composition and properties wherever it is found.
Every day you use products containing substances that were prepared by chemists.
Yep!
Sunlight
Energy given off by the sun. Thus, sunlight does not contain matter, which means it is not a chemical.
Metric system
System of measurement that scientists and health professionals throughout the world use.
International system of units (SI)
Modification of the metric system, which is now the official system of measurement throughout the world except for the U.S.
Units of measurement (metric)
Length: meter (m) Volume: liter (L) Mass: gram (g) Temp: degree Celsius (C) Time: seconds (s)
Units of measurement (SI)
Length: meter (m) Volume: cubic meter (m^3) Mass: kilogram (kg) Temp: kelvin (K) Time: seconds (s)
Length
1m = 100 cm.
1m = 39.4 in.
1m = 1.09 yd.
2.54 cm = 1 in.
Volume
The amount of space a substance occupies.
1 L = 1000 mL
1 L = 1.06 qt.
946 mL = 1 qt.
Mass
A measure of the quantity of material it contains.
1 kg = 1000 g
1 kg = 2.20 lb.
454 g = 1 lb.
kilo-
1 thousand
centi-
1 hundredth
mili-
1 thousandth
Measured numbers
The numbers you obtain when you measure a quantity such as your height, weight, or temperature.
Significant figures
In a measured number, all the digits including the estimated digit.
A number is a significant figure if it is…
- Not a zero
- A zero between nonzero digits
- A zero at the end of a decimal number
- In the coefficient of a number written in scientific notation.
A zero is not significant if it is…
- At the beginning of a decimal number
- Used as a placeholder in a large number without a decimal point
Exact numbers
Numbers obtained by counting items or using a definition that compares 2 units in the same measuring system.
Significant figures in multiplication or division
The final answer is written so it has the same number of significant figures as the measurement with the FEWEST SIGNIFICANT FIGURES.
Significant figures in addition or subtraction
The final answer is written so it has the same number of decimal places as the measurement with the FEWEST DECIMAL PLACES.
micro-
one millionth
Cubic centimeter
The volume of a cube whose dimensions are 1 cm on each side.
1 cm^3 = 1 cc = 1 mL
that’s it
Conversion factor
one of the quantities is the numerator, and the other is the denominator.
Ex. of a conversion factor: 1 hr = 60 min
60min/1hr and 1hr/60min
When is it exact vs significant figures
English to English = exact
Metric to Metric = exact
English to Metric= significant figures
Metric to English= significant figures