Matter
Light, sound, and heat are generally not classified as matter because they lack these two defining characteristics
Mass and volume
If the base is the same, then what do you do to the exponents when multiplying and dividing
When you have a number in scientific notation, how can you tell the number of significant figures just by looking at it?
Look at the number of digits in the coefficient
What type of property is welding?
A sample contains two or more substances that are visibly distinguishable, such as sand mixed with iron filings
Heterogenous mixture
What has to be true so that you can add or subtract the coefficients in scientific notation together
The exponent has to be the same
What is the difference between trailing and leading zeroes?
Leading zeroes are typically never significant, while trailing zeroes are typically always significant
Explain the rounding rules
5 and up means to round up and 4 and below means to round down
Two clear liquids are mixed and a solid suddenly forms. This is strong evidence that this type of change has occurred
Chemical change
In scientific notation, what numerical values must the coefficient be in between?
They should be in between 1 and 10
How are addition and subtraction problems different from multiplication and division problems in regard to significant figures?
In addition and subtraction, you need to pay attention to the number of decimal places (digits after the decimal point), while for multiplication and division, pay attention to the number that has the lower number of significant figures in general
Round 7.995 x 10^-2 to 3 significant figures
8.00 x 10^-2
A mixture can be separated by physical methods because its components retain these characteristics
Chemical identities and properties
(6.7 x 10^8) - (2.35 x 10^7)
Bonus points for correct number of significant figures!
6.465 x 10^8
6.5 x 10^8
Round 9.995 to 3 significant figures
1.00 x 10^1 or 10.0
Name all six phase changes and how they happen
(Ex. liquid to gas is ____, gas to liquid is ____, etc.)
Liquid to gas is evaporation, Gas to liquid is condensation, Liquid to solid is freezing, Solid to liquid is melting, Solid to gas is sublimation, Gas to solid is deposition
A sample contains O2 molecules, CO2 molecules, and individual Ar atoms. There are no chemical bonds between the different types of particles. How should the sample be classified and why?
A mixture of elements and compounds and this is a mixture because there are multiple different substances physically present together rather than chemically combined into a single substance
(9.6 x 10^-3) / (1.2 x 10^5)
Bonus points for correct number of significant figures!
8 x 10^-8
8.0 x 10^-8
What is 105.67 - 2.3?
103.4
If you are given these, you MUST include them to get full credit on whatever question you are solving along with showing your work
Include the units!