The periodic table is arranged in order of increasing atomic

number

Number of protons in an atom

Z

http://www.pbs.org/wgbh/nova/kaboom/elemental/images/periodic.map

An individual atom is

electrically neutral

An individual atom is

electrically neutral

How manyHow many protonsprotons andand electronselectrons

are in anare in an oxygen atom?oxygen atom?

How manyHow many protonsprotons andand electronselectrons

are in anare in an oxygen atom?oxygen atom?

http://www.pbs.org/wgbh/nova/kaboom/elemental/images/periodic.map

protonsprotons = 88electronselectrons = 8

protonsprotons = 9292electronselectrons = 92

Total numberTotal number of of protons protons andand

neutronsneutrons in an atom of a given in an atom of a given

isotope isotope

Mass NumberMass Number

Mass number is the number of protons and neutrons in the nucleus of an isotope.

Nuclide p+ n0 e- Mass #

Oxygen - 10

- 33 42

- 31 15

8 8 1818

Arsenic 75 33 75

Phosphorus 15 3116

A = 12

A = 238

A xz

Mass #

At. #

Write the symbol for the atom Write the symbol for the atom

that has anthat has an atomic number of 9 and aand a mass

number of 19.

19F9

How many electrons and how

many neutrons does the atom

have?

How many electrons and how

many neutrons does the atom

have?

19F99

How many electrons and how many neutrons

does the atom have?

How many electrons and how many neutrons

does the atom have?

19F99

number of neutrons = mass # - at. #

# of neutrons = A- Z

A= 19

Z = 9

# of neutrons = 19 - 9

= 10 neutrons = 10 neutrons

31X15

173X7070

Identify the element

66 protons protons

6 neutrons

9292 protonsprotons

146146 neutronsneutrons

All atoms of the same element do not necessarily have the same

number of neutrons in their nuclei

Atoms of the Atoms of the samesame

elementelement that have that have different numberdifferent number of of

neutronsneutrons

Atoms of the Atoms of the samesame

elementelement that have that have different numberdifferent number of of

neutronsneutrons

Isotopes…Again Isotopes…Again (must be on the test)(must be on the test)

Isotopes are atoms of the same element having different masses due to varying numbers of neutrons.

Isotope Protons Electrons Neutrons Nucleus

Hydrogen–1

(protium)

1 1 0

Hydrogen-2

(deuterium)

1 1 1

Hydrogen-3

(tritium)

1 1 2

When an atom losesloses or gains an electron

More More protonsprotons than than

electronselectrons

positive charge positive charge ++

CATION

                                        

More More electronselectrons than than protonsprotons

negative negative charge charge --

ANION

How many p+, e- and neutrons are

present in the following atom or ion?

24 Mg12

24 Mg12

MgMg atomatom – – neutral neutral 12 p+, 12 e-12 p+, 12 e-

If it loses 2e- ??? If it loses 2e- ??? What is it’s What is it’s

charge?charge?# of p+ = +12# of p+ = +12# of e- = -10# of e- = -10

+ 2

24 Mg 2+

12

Magnesium

cation

Write the chemical symbol for the ion with 9 protons

and 10 electrons

19F

-19

# of neutrons = 27 - 13 = 14

27Al

+3

Write the chemical symbol for the ion

with 7 protons and 10 electrons

14N-3

7

How many protons and electrons are present in

the S-2 ion?

32S-21616

Metal Initial Appearance

   

   

   

MetalCu(NO3)2

Cu+2 Mg(NO3)2 Mg+2 Zn(NO3)Zn+2 AgNO3 Ag+

Cu        

Mg        

Zn        

Initial Appearance of Each Metal

Metal Reactivity