SCIENCE MIDTERMS

study for Tuesday keep adding notes

what tool is used to measure the mass of an object

digital balance

tool to measure temperture

thermometer

basic metric unit of length

meter

mass is

the amount of matter in a object

what should you do when there is an accident in the lab

tell the teacher

what are building blocks of matter

atoms

the length of a highway would most likely be measured in

kilometers

chemical symbol for oxygen

O

write chemical reaction for carbon dioxide

CO2

which oxygen or carbon dioxide is a element

oxygen

density of water

1.0 g/ml

how do know if something will float in water

if it has a density less then water

round to nearest tenth 444.444 , 33.33 , 55.55

444.4 , 33.3 , 55.6

definate shape and volume

solid

no definite shape or volume

gas

have water molicules have most energy

gas

electrical charge of proton

positive

electrical charge of neutrons

netural / no charge

electrical charge of electrons

negitive

what is atomic number

total number of protons

the small positively charged center of atoms called the

nucleus

in a neutral atom , the number of protons must equal the number of

electrons

list noble gases

He , Ne , Ar , Kr , Xe , Rn , Og

are the noble gases reactive

no

what part an atom is involved during chemical bonding

electrons

where are metals found on the periodic table

left side and center

in a chemical equation , the arrow represents the world

yeild

a form of shorthand using symbols and formulas to represent a chemical reactions is

chemical equation

stong base = ph of

8-14

strong acid = ph of

0-6

neutral substance has ph of

7

universal solvent

water

a substance that changes color in the in the presence of an acid or base is called a

indicator

mass of proton

1.0 amu proton

mass of neutron

1.0 amu neutron

mass of electrons

0.54 amu

where were protons found in

the nulecus is where protons are found

where are electrons in the atoms

electron cloud

small center core of an atoms

nucleus

most reactive metals found in

group 1 and 2

list 3 properties of metals

conductors , malleable , luster

3 ways in which the solution rate increased are

crush , heat , stir

examples of chemical reactions include

digestion and combustion

solid to liquid

melting

liquid to solid

frezzing

air , saltwater , and raisin bran are ex of

mixtures

3 properties of acids

sour , turns red , 0-6

3 properties in bases

bitter , turns blue , 8-14

freezing point of water

0 c

boliling point of water

100 c

kilo

1000

centi

1/100

milli

1/1000

matter is anything that has

a mass and takes up space

an educated guess

hypothisis

in a controlled experiment , the factor being tested or changed is the

independent cause

pure water is classified as a

compound

which has most amount of mass electrons , protons , neutrons

protons

most reactive metals

alkinine

most reactive non metals

halagens

least reactive elements

noble gases

signs of chemical change

color change , fizzy , changes temperature

why does heated gas rise

hot air gas is less dense than cold air

instruments would be needed to find a density of an object

triple beam Balance

why does oil float on top of water

oil is less dense than water

homogeneous

looks the same all through out

components are not visible

single phase

same proportion in every sample

often called solutions

heterogeneous

componets often visable

2 or more phases

proportions vary by sample

not evenly distributed

often call suspensions

mixture

substances can be physically mixed but not bonded

each ingredient keeps its original properties

has a variable ratio

compound

atoms are chemically bonded together

becomes a new substance with its own properties

can only be separated by Chemical reactions

has a fixed ratio

independent variable

is the one you change to see what happens

it is a factor you are testing

dependant

what you measure or observed to see the results

it depends on the changes you make to the independent variable

controlled variable

the thing you keep exactly the same to make sure the test is fair