Unit 4 - Chemistry 9

Alpha, Beta, Positron Emission and Gamma Greek Letters

Alpha, Beta, Positron Emission and Gamma Symbol

4/2 a,

0/-1 e

0/+1 e

Y

Alpha, Beta, Positron Emission and Gamma: how is the atomic number changed?

-2

+1

-1

Same

Alpha, Beta, Positron Emission and Gamma: How is the mass number changed?

-4

same

same

same

Alpha, Beta, Positron Emission and Gamma: amount of energy

low

medium

medium

high

Alpha, Beta, Positron Emission and Gamma: stopped by

Paper

Aluminum

Aluminum

Lead

Half life: time/time

1. take time divided by time to get the half life

2. divide by 2 the number of half lives (if there are 4 half lives, divid the mass by 2 four different times)

Half life: mass/mass

1. Divide starting mass by two till you get the after mass

2. Divide the time by two the number of times the mass was divided (if you divided the mass 3 times, divide the time 3 times)

Properties of metal and nonmetals

Metal: Good conductors, luster, malleability, ductile most are solid at room temp, except mercury

Nonmetals; Poor conductors, brittle solids, most gasses at room temp, except bromine

Atomic radius

Total distance form an atoms nucleus to the outermost electron orbital

It increases as it goes down and decreases as you go to the right

Electronegativity

Measure of an atoms ability to attract shared electrons to itself

Decreases as it goes down and increases as it goes right

Ionization energy

The amount of energy needed to remove a electron from an isolated atom or molecule

Decreases as it goes down and increases as it goes right

How light is emitted

When an electron gains energy as it moves up from the ground state to the excited state, and when it falls back down it creates light by releasing energy in the form of photons.