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