chem chapter 3

When is scientific notation used?

express very big or very small numbers

when you are putting a number into scientific notation and the number becomes bigger than the original, is the exponent negative or positive

negative

when you are putting a number into scientific notation and the number becomes smaller than the original, is the exponent negative or positive

positive

what do line graphs. show

continuous change

do you use the line of best fit or connect the dota method in chem

line of best fit

what are the 5 elements of a good graph

1. title (x vs y)
2. labeled axis w units
3. neat
4. use available space
5. line of best fit

x and y are directly proportional. if X goes up, what happens to Y

Y goes up (and vice versa)

x and y are inversely proportional. what happens to Y when X goes down

Y goes up

define accuracyy

how close the measurements are to the actual value

define precision

how well the measurements can be repeated —> clumping

t/f precision only involves one trial

f it involves many trys/trials

what is systemic error

reduces accuracy; error with the instrument/tool ; like the clock always being 3 minutes fast

what is a random error

reduces precision; error made by a person

When are zeros significant?

-zeros in the middle of a number
-zeros at the end of a number with a decimal point

What is an exact number?

number derived by counting or by definition

what is a measured number?

a number determined by using a measuring device

What is the sig fig rule for addition and subtraction?

answer should have the amount of decimal places as the least amount used

What is the sig fig rule for multiplication and division?

answer should have the same amount of sig figs as the least amount used

Kilo value

10^3

Deci value

10^-1

Centi value

10^-2

Mili value

10^-3

Micro value

10^-6

Nano value

10^-9

formula for area

Length x Width

Formula for volume

length x width x height

What is standard temperature

273 K and 0'C

What is standard pressure

1 atm, 101.3kPa, 760 mm Hg

Converting K to C equation

C= K - 273

Converting C to K

K= C + 273

Celsius/Farenheit conversion

F= 1.8C + 32

Equation for density

Mass/volume

What are the two typical units for density

g/cm^3 (solids) and g/mL (fluids)

2 methods of finding volume

1. Formula
2. Water displacement

What is the density of water

1 g/mL or 1 g/cm3

What is the SI unit for the amount of a substance

Mole

6.02x10^23 particles =

1 mol

T/f number of particles = number of atoms

T

1 mL= ?L

0.001 L

1ml=?cm^3

1

1 L= ?dm^3

1

1 cm= ?mm

10

How many cm are in an inch

2.54

Which standard unit has a prefix

Kilogram

What are the standard units for volume

Cm^3 and mL

What are the standard units for length

Meters (m)

What are the standard units for mass

Grams (g)

If you have a cup of 5 mL of water, should you remeasure it in a 10 mL graduated cylinder or 20 mL graduated cylinder

10 mL bc dealing with a smaller range tool will be easier to read

Is density extensive or intensive

Intensive

Is density a physical or chemical property

Physical

What is the conversion order when dealing with mols, atoms, mass, and particles

Mass (g), mols (mol), particles, atoms

Percent error formula

E-A/A X 100

If a graph is a hyperbola, is it inverse or direct

Direct

If a product is a constant, is it inverse or direct

Inverse

Is density inverse or direct

Inverse