Chemistry

K mass number

39

Cr mass number

52

How many electrons are in neutrally charged c-14 c-12 c-13?

6

How many neutrons are in c12 c13 and c14?

6,7,8

K charge

+1

Cr charge

+3

Examples of anion is oxygen and chlorine

0^-2 equals oxide anion Cl^-1 equals chloride anion

Hydrogen 3

1 proton 1 electron 2 neutrons

Hydrogen 2

1 proton 1 electron and 1 neutron

Hydrogen 1

1 proton one electron 0 neutron

Hg # of neutrons

120

K # of electrons

18

K # of protons

19

K atomic number

19

K # of neutrons

20

Hg mass number

200

Cr # of electrons

21

Cr # of protons

24

Cr atomic number

24

Cr # of neutrons

28

Element Hg atomic number

80

Hg # of electrons

80

Hg # of protons

80

Who was Democritus, 400B.c

A a Greek philosopher who was the first person to think about an atoms existence and believed that matter was composed of tiny indivisible particles called atoms he had no experimental evidence to support his thoughts

Who was John Dalton(1766-1844)

A meteorologist that had experimental evidence to support his theory

+^2

Charge

What was Dalton's first theory

All elements are composed of individual particles called atoms

Don't forget

All percentages must equal hundred all decimals equal 1

What is a periodic table

An arrangement of the elements according to similarities and their properties

Neutral atoms

An atom is considered neutral when it has the same number of electrons and protons (p+ =e-)

What is an ion

An atom or group of atoms that has a positive or negative charged ions form when an atom gains or loses electrons

What is an ion

An atom or group of atoms that have a positive or negative charge

Cations

An atom or group of atoms with a positive charge, metals lose electrons to become cations, have the same name as the element that forms them but different chemical properties

Ion

An atom or group of atoms with a positive or negative charge

Atomic mass

An average of masses of different isotopes

How to write ions

And ionic charge is written as a sign positive + or negative - followed by a number the number represents the amount of electrons gained or lost

Anion

Atom or group of atoms with a negative charge, non metals tend to form ions by gaining electrons, the name of the anion is the first syllable of the element "ide" on the end

15.999

Atomic mass

9.01

Atomic mass

Example of neutrons

Atomic mass number is 16 and its atomic number is 8 the number of neutrons will be 16-8 which is 8

Beryllium

Atomic name

4

Atomic number

8

Atomic number

How is the periodic table arranged

Atomic number

S^-2

Atomic number 16 mass number 32 number of protons 16 number of neutrons 16 number of electrons 18

Cl^-1

Atomic number 17 mass number 35 number of protons 17 number of neutrons 18 number of electrons 18

Ca^+2

Atomic number 20 mass number 14 number of protons 20 number of neutrons 20 number of electrons 18

N^-3

Atomic number 7 mass number 14 number of protons 7 number of neutrons 7 number of electrons 10

Proton

Atomic number represent this

Dalton

Atoms combine in whole number ratios

What was Dalton's third theory

Atoms of different elements mixer combine in whole number ratios

What was Dalton's second theory

Atoms of the same element are identical the atoms of any one element or different from those of another

Isotopes equals

Atoms with different number of neutrons

Isotopes

Atoms with the same number of protons but different number of neutrons they are chemically and have different mass numbers, written like this element - mass number

What is atomic mass?

Average weight of all the element isotope

How is each element represented on the periodic table

By a symbol place in a square

What was Dalton's fourth theory

Chemical reactions occur when atoms separate join or arranged in a chemical reaction. atoms of one element never change into another

Dalton 2

Chemical reactions occur when atoms separate, join, or rearrange

Isotopes

Different numbers of neutrons create these different versions

Thompson

Discovered the electron

What else did JJ Thomson do

Discovered the electron he believed that the atom was a solid positive sphere with electron shoved into the side of it his modelwas said to resemble a popular English dessert called plum pudding

Chadwick

Discovered the neutron

Goldstein

Discovered the proton

Who made the periodic table

Dmitri mendeleev

Describe where the metals are found on the periodic table

Except for hydrogen on the left side are metals

Electrons

For a neutral atom to charge on these particles balance out the charge on proton

Atomic number 2

For neutral elements(no charge)the number of protons equal number of electrons. The number of protons will never change for any element(identifies them)

What is each group on the periodic table called and how many of them are there

Groups and their 18

Democritus

Had no evidence to support an atoms existence

Which is the only non-metal element that is not located with the rest

Hydrogen

Gained

In order for a neutral atom to attain a negative charged electrons must be what?

What did JJ Thompson do (1859-1940)

In the tube was an inert gas and two plates a positive and a negative, the particles in the gas were attracted to the positive plate there for the positive particle is attracted to the negative particle

What are c12 c13 c14 called

Isotopes

9

Mass number

Neutrons is

Mass number - atomic number

What was Ernest rutherford observation

Most of the alpha particles went through he concluded the atom is mostly empty space, few particles were deflected at small angles he concluded the alpha particle came close to something small and positive, very rarely particles were deflected at large angles he concluded the Alpha particles had a small very dense and positively charged the center of the nucleus

Gaining electrons equals

Negative charge

James Chadwick(1891-1974) discovered what

Neutrons

Finding the number of neutrons

Neutrons equal mass number - atomic number

Mass number

Number of protons and neutrons combined always a whole number

To find the average atomic mass you need to know

Number of stable isotopes, mass of each isotope, natural percentage abundance of each isotope

Example of atomic number

Oxygen atomic number is 8 therefore 8 protons are in oxygen nucleus

What is each row on the periodic table called and how many of them are there

Periods and there are 7

Losing electrons equals

Positive charge

Eugene Goldstein(1850-1930) discovered what?

Proton

Atomic number is

Protons equals electrons neutral atoms

Sub atomic particles

Protons neutrons and electrons are called this

Mass number

Protons plus neutrons

Mass number is

Protons plus neutrons which equals rounded atomic mass

Mass number equals

Protons+neutrons

Dalton 4

Provided evidence supporting the existence of atoms

Atomic mass

Read right off the periodic table the number will have a demical, it is the average weight of all elements isotopes

What ability did the periodic table have

Relate the elements in a systematic logical way

Dalton 3

Said that atoms of the same element are identical but the atoms of one element are different than those of another

Rutherford

Said that the atom was mostly empty space

How many protons are in c12 c13 and c14?

Six

Example of cations sodium and calcium

Sodium Na^+1 equals sodium cation and calcium Ca^+2 equals calcium cation

What is another name for the zigzag line

Staircase

Proton

Symbol P+ charge +1 relative mass one location in the nucleus

Electron

Symbol e- negative charge - 1 relative mass one/1840 location in the electron cloud outside the nucleus energy levels

Neutron

Symbol n charge 0 relative mass one location in the nucleus

Be

Symbol of element

Where are the metalloids found and how many are there

The elements that border the zigzag line and there are nine

Atomic number

The number of protons in the element always a whole number

Atomic mass occurs with decimal points because

They are an average of different isotopes

Non metals

This group of elements tend to gain electrons

Metals

This group of elements tend to lose electrons

Describe where the nonmetals are found in periodic table are found

Upper right corner

What did Ernest rutherford do

Use the gold foil experiment to discover the nucleus shot a high energy beam of alpha particles into gold foil

Thompson

Used the cathode ray tube to support his findings

Rutherford

Used the gold foil experiment to discover the nucleus

What are the two ways in which an ion can be made

When an atom gains or loses electrons

Positive

When electrons are lost a this charge is obtained