GOB Exam 1

Scientific notation

a way to write very large or small numbers

ex. 1.2x10¯4

SI base unit for mass

gram (g)

SI base unit for length

meter (m)

SI base unit for volume

Liter (L), Cubic meter (m˘3)

SI base unit for time

Seconds (s)

SI base unit for temperature

°C, Kelvin (K)

SI base unit for amount of substance

mole (mol)

milli-

(m) 0.001

10¯3

kilo-

(k) 1000

10^3

milligrams in a gram

1000 m in 1 g

0.001 g in 1 m

kilograms in a gram

0.001 kg in 1 g

1 kg in 1000 g

Density

mass/volume

measuring density of an object

determine volume using displacement, determine mass with a scale, m/v

measuring density of a liquid

measure v, measure m, m/v

specific gravity

density of a liquid relative to water

pure substance

matter that has a fixed/definite composition

ex. H2O, C2H6O

What is an element?

A pure substance that contains ONE type of atom.

What can be found on the periodic table?

Elements.

Give an example of an element.

Cu (Copper), Al (Aluminum), or H (Hydrogen).

heterogenous mixture

not a constant composition (components not uniformly distributed)

ex. trail mix, soupy mixture

homogenous mixture

constant composition (uniformly distributed. cant be seen separately)

ex. honey, tea, blood, medicine

chemical change

rearranging atoms to make a new substance

ex. rusting of iron, combusting of methane gas

physical change

can preform on a compound without changing the chemical composition (no new substance made)

ex. melting ice, boiling, freezing water

difference between physical and chemical change

chemical change: a new substance is created

physical change: no new substance made

major units of energy

cal and J

chem vs food cal

food cal means energy

chem cal means heat

food cal vs chem cal conversion

1 food cal = 1000 chem cal

value of energy for a fat

9 kcal/g

value of energy for a protein

4 kcal/g

value of energy for a carbohydrate

4 kcal/g

energy change for heating/cooling

E=mSHΔT

energy = mass X specific heat X temperature change

energy change for melting/freezing

E=mΔHf

energy = mass X heat of fusion

heat of fusion

80cal/g

Where are metals found on periodic table

left

where are non-metals found on periodic table

right

anatomic number

top left (in the box)

indicates # of p+ and e¯ in an atom

mass number

bottom middle (in the box)

mass of atom in amu's

how to figure out # of neutrons?

mass number - atomic number

alpha particles

α, 4/2 He

stopped by piece of paper & skin

MOST dangerous if ingested

beta particles

β, 0/-1 e

stopped by lab coats and rubber gloves

gamma ray

γ, 0/0 γ

stopped by lead or concrete

geiger counter

measures radiation in curies or becquerel's

measures the # of disintegrations in 1 sec for 1g of radium

rad

radiation absorbed dose

amount of radiation absorbed by 1g of body tissue

REM

measures biological effects of different types of radiation

alpha does most damage according to rem

half-life

the time it takes for ½ of the concentration of the isotope to react & decay

ionic compound

metal & nonmetal

hydroxide

OH¯

nitrate

NO¯₃

carbonate

CO¯²₃

bicarbonate

HCO¯₃

sulfate

SO¯²₄

phosphate

PO¯³₄