Atoms

Front 1

matter

Back 1

everything that has mass and takes up space

Front 2

mass

Back 2

a measure of the amount of matter in an object

Front 3

atom

Back 3

a small particle that makes up all matter

Front 4

an atom is made up of mostly...

Back 4

empty space

Front 5

the parts of an atom is

Back 5

electron, nucleus, neutron, proton

Front 6

definition of weight

Back 6

the gravitational force exerted on an object

Front 7

the definition of volume

Back 7

the amount of space an object takes up

Front 8

Democritus (460-370 BC)

Back 8

the greek philosopher was the first to use the word atom. He believed atoms were solid spheres with no holes. he proposed if u cut paper over and over until you cant anymore you had one atom that can not be divided.

Front 9

the law of conservation of mass

(Antoine Lavoisier 1743-1797)

Back 9

Lavoisier heated a container of mercury oxide and the powder turned into a silver liquid and gas ( gas was oxygen). the law says mass of the product is the same as the mass of the starting material.

Front 10

the law of definite proportions

(J.L. Proust 1799)

Back 10

Proust completed experiments that showed any pure compound contains the same elements in the same proportion and that the law applies to every compound.

Front 11

What is the triple beam balance used for?

Back 11

to measure mass or amount of a material contained

Front 12

How do you know when the final balance has been reached on a triple beam balance?

Back 12

when the grams are back to zero

Front 13

the definition of chemical reaction

Back 13

a process in which atoms of the starting material rearrange to form a new product with different properties

reactants-------------------product
(what you start with)---------(what you end with)

Front 14

the equation iron+oxygen=iron oxide

Back 14

Fe+O= FeO

Front 15

the equation for

baking soda + vinegar= sodium + acete + water + carbondioxide

Back 15

NaHCO + CHCOOH = CHOONa + H20 + CO2

Front 16

name the 5 principles of the atomic theory

(Dalton)

Back 16

1. All matter is made up of atoms.

2. Atoms are neither created nor destroyed in chemical reactions.

3. Atoms of different elements combine in whole- number ratios.

4. Each element is made of different kind of atoms.

5. The atoms of different elements have different masses and properties.

Front 17

Dalton's atom

Back 17

a simple neutral sphere of indivisible matter that was the same throughout

Front 18

Thomson's atom

Back 18

His discovery of electrons showed atoms were not indivisible but contained negative electrons and positive charges.

Front 19

Rutherford's atom

Back 19

His experiments explained most of the atoms mass is squeezed into the nucleus and the remaining space the electrons moved around the nucleus in any size of a diameter.

Front 20

Bohr' Atom

Back 20

he believed that the electrons had a certain diameter of an orbit

Front 21

Electron cloud atoms

Back 21

this is the current model in which electrons occupy a space around the nucleus but it is difficult to tell where an electron is

Front 22

explain the scientist Democritus

Back 22

he was the first to use the word atom and described the atom as paper not being able to be divided anymore. his model of the atom was a solid sphere.

Front 23

explain the scientist Lavoisier

Back 23

he made the law of conservation of mas and the mass of the product is the same as the starting material

Front 24

explain the scientist Dalton

Back 24

He invented symbols for elements, the 5 principles in an atomic theory, and measured reactants and products of chemical reactions.

Front 25

explain the scientist Rutherford

Back 25

Rutherford did the gold foil experiment and expected to fid out in the experiment that electrons & (+) charges were mixed but the result of the evidence was the (+) charges were mixed evenly because the particles bounced off the foil.

Front 26

explain the scientist Proust

Back 26

Proust invented the principle of any pure compound always contains the same elements in the same proportion by mass which came to be known as the law of definite proportions.

Front 27

explain the scientist Thomson

Back 27

Thomson was the first to use the name electron. this was found because the cathode ray bent and proposed that there must be positive charges to balance out the negative charges.

Front 28

explain the scientist Chadwick

Back 28

In 1932 Chadwick was the first to use the word neutron and proved that there was another undiscovered particle (the neutron) in an atom.

Front 29

explain the scientist Bohr

Back 29

Bohr believed electrons can move in circles from a certain diameter around the nucleus.

Front 30

what is a spectral line?

Back 30

a single wavelength of light that can be seen when the light from an excited element is passed through the prism

Front 31

explain energy levels

Back 31

they are the regions of space that electrons can move around the nucleus

Front 32

what is an element?

Back 32

a pure substance made from atoms that all have the same number of protons.

Front 33

what is an atomic number?

Back 33

the number of protons in the atom of an element

Front 34

what is a mass number?

Back 34

the sum of the number of protons and neutrons the atom has

Front 35

what is an isotope?

Back 35

atoms of the same element that contains different numbers of neutrons

Front 36

what is the average atomic mass?

Back 36

it is the weighted average mass of the mixture of an element' isotope

Front 37

what is an ion?

Back 37

an atom that is no longer neutral because it has gained or lost electrons. Ions form ionic compounds.