Q: What’s an atom?Q: What’s an atom?

The smallest piece of matter that still has all the properties and characteristics of that type of matter

EX. An atom of gold still has the same chemical and physical properties as a chunk of gold

Q: What’s an atom?Q: What’s an atom?

Brownian Motion

Perpetual movement of particles (atoms jiggling/vibrating)

Named after Robert Brown (Scottish botanist).

Q: What does an atom look like?

An atom is mostly empty space

Atoms have a small, dense nucleus at their center

Atoms contain what we call subatomic particles (3 subatomic particles)

Q: What does an atom look like?(3 subatomic particles)

Electron (symbol e-) Location- electron cloud (outside nucleus)

Charge- negative (each electron has a -1 charge)

Relative mass- 1/1840 1/1840 the size of the other particles = SMALL

Q: What does an atom look like?(3 subatomic particles)

Proton (symbol p+) Location- nucleus

Charge- positive (each proton has a +1 charge)

Relative mass- 1

Q: What does an atom look like?(3 subatomic particles)

Nucleus (symbol n0) Location- nucleus

Charge- neutral (each neutron has zero charge, not charged at all!)

Relative mass- 1

Draw a picture of an atom below. Label each of the three subatomic particles, as well as the nucleus and electron cloud.

Q: What is the overall charge of the nucleus in an atom? Why?

Nucleus is made of protons and neutrons (p+ and n0)

Since the only charged particles are protons and they have a positive charge, the overall charge is positive

Break Time

Structure of the Atom Worksheet (ChemQuest 8) with questions Use the diagrams and information on the

front of the sheet to answer the questions on the back.

Q: What is the Periodic Table?

Where we can look to find elements Any element in the world is found here. If

it’s not here, it’s not an element.

For example: Hydrogen and oxygen are found on the PT (H

and O), they are both elements. Water is made of these elements (H2O), but is

not found on the PT. Water is a COMPOUND, not an element

Q: What is the Periodic Table?

The table is organized based on physical and chemical properties/characteristics of elements such as: What will happen when it is mixed with a certain

chemical? How many of each subatomic particle are

present? What state of matter is it at room temperature? What does it look like (shiny, dull, etc)? How big is an atom of that element?

Q: How do I read the periodic table?

First, you must realize that each box contains information about ONE ELEMENT

Q: How do I read the periodic table?

The smaller number in each box (usually at the top) is called the atomic number. Tells us how many p+ an atom of that element

has Tells us how many e- an atom of that element

has *** This is true ONLY if the atom has an overall

NEUTRAL CHARGE

Atomic Number

8

O15.999

Oxygen

Atomic Number

Q: How do I read the periodic table?

The larger number (usually at the bottom) represents the atomic mass. Measured in amu (atomic mass units) Tells us the total number of p+ and n0 in an

atom How can I use this to find JUST the number of

n0? Atomic mass – Atomic number = # n0

Atomic mass MUST be rounded to the nearest whole number

Atomic Mass

8

O15.999

OxygenAtomic Mass (amu)

Q: How do I read the periodic table?

Chemical Symbol Usually only one or two letters Some have three letters- these are manmade

and will likely get renamed. First letter is always capital, second is always

lowercase Some symbols are based on the Latin names

for the element Ex. Aurum – gold – Au

Ferrum – iron – Fe

Chemical Symbol and Name

8

O15.999

Oxygen

Chemical Symbol

Chemical Name

Example: Find the element Bismuth (Bi) on your PT.

Atomic Number: 83Atomic Mass: 207 (approx)Symbol: Bi# p+ = 83# e- = 83# n0 = 124 (207 – 83)

Agenda Items

Atomic Math Challenge- due tomorrow