chem 1a ch e

international system of units (SI)

a measurement system used by scientists that’s based on the metric system

meter

distance traveled by light in a vacuum

mass

measure of the quantity of matter, measured in kg and based off of planks constant

weight

the measure of gravitational pull of its matter

temp

the measure of the avg amount of kinetic energy of the atoms or molecules that compose matter

heat

thermal energy transfer, determined my the temp, from hot to cold objects

kelvin scale

works by assigning 0 degrees kelvin to the temp that matter essentially stops, the coldest it can be, called absolute zero. K is the same size as celcius, only difference is the starting point.

formula to get celcius from farenheit

C = (F-32)/1.8

formula to get kelvin from celcius

K = C + 273.15

exa, E

10¹⁸

peta, p

10¹⁵

tera, T

10¹²

giga, G

10⁹

mega, M

10⁶

kilo, K

10³

deci, d

10^-1

centi, c

10^-2

milli, m

10^-3

micro, µ

10^-6

nano, n

10^-9

pico, p

10^-12

femto, f

10^-15

atto, a

10^-18

derived units

combinations of other units

volume

measure of space, any measure of length to the power of 3

accuracy

refers to how close the measured value is to the actual value

precision

refers to how close a series of measurements are to one another or how reproducible they are

significant figures

none-placeholding digits

density

ratio of mass and volume

formula for density

d = m/v

intensive property

independent of the amt of the substance, depends on the type

extensive property

depends on the amt of the substance

energy

capacity to do work

work

defined as the action of a force through a distance

kinetic energy

energy associated with motion

potential energy

energy associated with its position or composition

formula for kinetic energy

KE = 1/2mv²

thermal energy

type of kinetic energy, arises from the motion of the individual atoms/molecules

law of conservation of energy

the idea that energy cannot be created or destroyed

chemical potential energy

primarily from electrostatic forces between the electrically charged particles that compose the atoms/molecules

1 cal = ? J

4.184 J

1 Cal = ? cal

1000 cal

exothermic

the change in energy is negative, the energy leaves and goes out

endothermic

the change in energy is positive, the thermal energy is gained

dimensional analysis

using units in calculations to guide solving problems

conversion factor

fractional quantity with the units we are converting from on the bottom and the ones converting to on the bottom