Chp 4.2- Structure of the Atom

Chp 4.2- Structure of the Atom

Pg. 108-112Pg. 108-112

Subatomic ParticlesSubatomic Particles

Light up your old tv screen. When the beam sweeps across your screen it lights up spots There are three

beams, one for each primary color of light

Red Green Blue

Particles in the beams are subatomic particles

Light up your old tv screen. When the beam sweeps across your screen it lights up spots There are three

beams, one for each primary color of light

Red Green Blue

Particles in the beams are subatomic particles

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Properties of Subatomic Particles

Properties of Subatomic Particles

Protons, electrons, and neutrons are subatomic particles

Protons - a positively charged subatomic particle that is found in the nucleus of an atomCharge is +1, Mass = 1

Electrons - a negatively charged subatomic particle that is found in the space outside the nucleusCharge is -1, mass = 1/2000Greek word means amber

Neutrons - a neutral subatomic particle that is found in the nucleus of an atom, no chargeMass is almost exactly equal to that of a proton (mass

= 1)

Protons, electrons, and neutrons are subatomic particles

Protons - a positively charged subatomic particle that is found in the nucleus of an atomCharge is +1, Mass = 1

Electrons - a negatively charged subatomic particle that is found in the space outside the nucleusCharge is -1, mass = 1/2000Greek word means amber

Neutrons - a neutral subatomic particle that is found in the nucleus of an atom, no chargeMass is almost exactly equal to that of a proton (mass

= 1)

Comparing Subatomic ParticlesComparing Subatomic Particles Protons, electrons, and

neutrons can be distinguished by mass, charge, and location in an atom

Protons and neutrons have almost the same massProtons have a positive

chargeNeutrons have no chargeBoth are found in the

nucleus

Protons, electrons, and neutrons can be distinguished by mass, charge, and location in an atom

Protons and neutrons have almost the same massProtons have a positive

chargeNeutrons have no chargeBoth are found in the

nucleus

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Comparing Subatomic ParticlesComparing Subatomic Particles Electrons have a mass about 2000

times smaller than that of a protonBut its charge is equal in size to and

opposite of the charge of a protonFound in the space outside the nucleus

Electrons have a mass about 2000 times smaller than that of a protonBut its charge is equal in size to and

opposite of the charge of a protonFound in the space outside the nucleus

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Atomic numberAtomic number

The atomic number of an element equals the number of protons in an atom of that element

Atoms of different elements have different numbers of protons

Can be used to refer to different elements

Atomic number is also the number of electrons for an atom because the charges are balanced

The atomic number of an element equals the number of protons in an atom of that element

Atoms of different elements have different numbers of protons

Can be used to refer to different elements

Atomic number is also the number of electrons for an atom because the charges are balanced

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Mass NumberMass Number Mass number - The sum of the protons and

neutrons in the nucleus of an atomMass # = # protons + # neutrons

To find the number of neutrons in an atom subtract the atomic number from the mass number# neutrons = mass # - Atomic #

Mass number - The sum of the protons and neutrons in the nucleus of an atomMass # = # protons + # neutrons

To find the number of neutrons in an atom subtract the atomic number from the mass number# neutrons = mass # - Atomic #

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IsotopesIsotopes Isotopes - atoms of the same element that have

different numbers of neutrons and therefore different mass numbers

Isotopes of an element have the same atomic number but different mass numbers because they have different numbers of neutrons

Every atom of oxygen has 8 protons but some atoms have 8 or 9 or even 10 neutrons Atoms with 8 have a mass number of 16 Atoms with 9 have a mass number of 17 Atoms with 10 have a mass number of 18

Isotopes - atoms of the same element that have different numbers of neutrons and therefore different mass numbers

Isotopes of an element have the same atomic number but different mass numbers because they have different numbers of neutrons

Every atom of oxygen has 8 protons but some atoms have 8 or 9 or even 10 neutrons Atoms with 8 have a mass number of 16 Atoms with 9 have a mass number of 17 Atoms with 10 have a mass number of 18

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IsotopesIsotopes With most elements it is hard to notice any differences in

the physical or chemical properties between the isotopes Hydrogen-1 only has 1 proton and no neutrons

Hydrogen-2 has 1 proton and 1 neutron which doubles its mass, water that contains hydrogen-2 is called heavy water.

With most elements it is hard to notice any differences in the physical or chemical properties between the isotopes

Hydrogen-1 only has 1 proton and no neutrons Hydrogen-2 has 1 proton and 1 neutron which doubles its mass,

water that contains hydrogen-2 is called heavy water.

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The EndThe End

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