Isotopes. Are All Atoms of an Element the Same? Not necessarily. Some atoms have an unequal number of protons and neutrons. We call these atoms isotopes.

Slides:



Advertisements
Similar presentations
Chemistry: The Nature of Matter.
Advertisements

Reviewing Subatomic Particles
The Atom.
Exceptions to the Rule…
IV. Isotopes 2 or more atoms of the same element having the same number of protons BUT different numbers of neutrons.
ABSOLUTE AGE Absolute dating- used to determine the age of a rock or fossil more exactly based on the properties of atoms An atom:
Absolute Dating Chapter 3, Sec.3. Process to find the approximate age of rocks or fossils.
4.3: HOW ATOMS DIFFER ATOMIC NUMBER
Mr. McMartin Beta Pod Science
Properties of nucleus 26.2 Binding energy and mass defect. UNIT 26 : NUCLEUS is defined as the central core of an atom that is positively charged.
Atomic Structure Section The Nucleus Nucleus- contains most of the mass of an atom – Protons & Neutrons contains most of an atom’s mass – Electrons-
Periodic table Groups – Columns down Alkali Metals Alkaline Earth Metals Halogens Noble gases Periods – Rows across Lanthanides Actinides Groups – Columns.
Atomic Structure Nucleus – contains protons and neutrons
Atomic Mass & Number Isotopes The Periodic Table.
Essential Question: How do atoms of the same element differ?
The Atom & the Periodic Table. Reading the Periodic Table.
Copyright © by Holt, Rinehart and Winston. All rights reserved. Section 3 How Atoms Differ.
Half Lifes. Atoms Proton Electron Cloud Neutron Atomic Number Number of protons – change this → change the element Hydrogen has one proton and one electron.
 Protons, neutrons, electrons too  Make up the atoms all around you!
4.2 The Structure of an Atom. Atom is the smallest particle of an element. Atoms cannot be divided into anything smaller.
Components of the Atom Nucleus: Nuclear Forces:
Chapter 11 The Atom.
How do atoms differ? Section 4.3.
Chapter 18 Lesson 2 Masses of Atoms
How Atoms Differ.
Atomic Mass Notes 5 Chapter 17-2.
The Atom.
ISOTOPES & AVERAGE ATOMIC MASS
The Atom The smallest particle into which an element can be divided and still retain all of the properties of that element.
Rutherford Experiment & Isotopes Mr. Rana 9/21/12.
Isotopes  Atoms with the same number of protons but different numbers of neutrons  Ex) Carbon 12 vs. Carbon 14  These atoms have a different mass 
Masses of Atoms Chapter 19-2 Pages
NOTES – 4.3: Atomic Number, Mass Number, Isotopes and Atomic Mass.
Chapter 3 Atomic Structure. The Structure Of the Atom Particle masschargelocation Proton1 AMU +1in nucleus Neutron 1 AMU 0in nucleus Electron 0 AMU -1.
 Atomic Number- the number of protons in the nucleus of an atom of that element  Ex: Hydrogen atoms have only one proton in the nucleus, so the atomic.
Chapter 5 Notes.  The atomic mass of an element is a weighted average mass of the atoms found in nature.  If you were to mass an oxygen atom, would.
Do Now: If a student’s grade is weighted per the table below, what would their grade be? WeightAverage Tests50%80 Classwork30%95 Homework20%85.
Atomic Structure Review
Isotopes. The Nucleus  The number of protons in the nucleus of an atom is unique to each type of element  BUT, the nuclei of the same type of element.
How Atoms Differ. a. Properties of Subatomic Particles ParticleSymbolLocationRelative Charge Relative mass Actual mass (g) Electron Proton Neutron.
Atoms Atom- the smallest part of an element Atoms of one element are different from another element. contains protons, electrons, and neutrons Atomic Mass.
Isotopes and Mass Number. Isotope Atoms of the same element with: Same number of protons BUT Different number of neutrons ELEMENT IS TO ISOTOPE AS DOG.
Journal #20 1. Who discovered the electron? 2. What did Rutherford discover?
Unit 3: The Atom. Atoms All matter is made of very tiny particles All matter is made of very tiny particles These particles have the same properties as.
Atomic Mass. Atomic mass Most of the mass of an atom is in the nucleus. Most of the mass of an atom is in the nucleus. The nucleus is where all of the.
Atomic Mass. Each element found on the periodic table of elements is given an atomic mass The atomic mass tells you the average mass of the atoms of an.
ELECTRONS. Review Electrons were discovered by ______________ Electrons have a ___________ charge Electrons are located…. Outside of the nucleus in an.
Chapter 8 Earth Chemistry Section – Atomic Number ► An atom of a specific element is different from other elements by the number of protons it.
Neutrons and Isotopes. NEUTRONS AND ISOTOPES Unlike the number of protons, the neutrons in the nucleus of atoms of the same element can vary. Atoms of.
Atomic Structure - Bellwork What experiment did Rutherford perform that identified positively charged nucleii in an atom? What do we call Thomson’s atomic.
Ch. 3-3a Distinguishing and Counting Atoms. POINT > Define Atomic Number POINT > Define Mass Number POINT > Describe and identify isotopes POINT > Determine.
Masses of Atoms and the Periodic Table. Atomic number To identify which element an atom is, we look at the number of protons. The number of protons in.
Essential Question: How do atoms of the same element differ?
Do Now: Match the scientist with their contribution to the atom A. Dalton1. Mass of electron B. Thomson2. atomic theory C. Milikan3. discovered electron.
Aim: How to Calculate the Average Atomic Mass?
Masses of Atoms.
Calculating Atomic Mass
Parts of the Atom PSSA: A/S8.C.1.1.
Isotopes.
Isotopes.
Unit 3 – Atoms, Ions, Isotopes
The Structure of Atoms Thanks to those 7 scientists (and many more) what do we know about atoms today?!
ISOTOPES Isotopes are atoms of the same element that have a different number of neutrons. They differ in mass, but the atom’s chemical behavior are.
Atomic Structure Chemistry.
Chapter 4 Atomic Structure 4.1 Defining the Atom
Atomic Mass.
Chapter 4 – The Structure of the Atom
How can we explain absolute dating?
Chemistry Chapter 3 Section 3
Presentation transcript:

Isotopes

Are All Atoms of an Element the Same? Not necessarily. Some atoms have an unequal number of protons and neutrons. We call these atoms isotopes. In an isotope, the number of protons in an element always remains the same. The neutrons change. Lets look at an example…

How are they different? Proton Electron Proton Electron This is a Hydrogen AtomThis is a Hydrogen Atom Isotope Neutron The isotope has 2 particles which means it has greater mass.

Properties of Isotopes Each element has a limited number of isotopes that occur naturally Some isotopes have unique properties because they are unstable

Properties of Isotopes An atom that is unstable means that the nucleus has the ability to change the numbers of neutrons that are in the nuclear space. Isotopes that are unstable are also called radioactive.

Properties of Isotopes Simply stated…Isotopes share almost all of the same physical and chemical characteristics. For example, Oxygen isotopes are colorless, odorless gases at room temperature (physical).

How Can We Tell One Isotope from another? Each element has a mass number which identifies the isotope of the element. Mass number = protons + neutrons in an atom Electrons have such small mass they are not included in this calculation

Naming Isotopes Lets go back to our earlier example of the hydrogen atom and the hydrogen isotope.

Name That Isotope! Proton Electron Proton Electron There is 1 proton and 0 neutrons so the name of this atom is Hydrogen-1 There is now 1 proton AND 1 neutron so the name changes to Hydrogen-2 Neutron

So How Do I Figure Out The Number of Protons And Neutrons? As an example, well look at the carbon isotope, with a mass number of 12 (found on the Periodic Table) Its called Carbon-12. Mass Number 12 - # Protons (atomic number) -6 Number of neutrons6

Try One Determine the number of protons, neutrons, and electrons in an aluminum-27 (Al). 13 protons, 14 neutrons, and 13 electrons How did we get the number of electrons? Its the same as the number of protons.

Lets Try One! Use what you know about Carbon-12 to create Carbon-13. Using your Periodic Table create Hydrogen-2 (H), Helium-3 (He), and Carbon-14 (C).

Where Have I Heard Carbon-14 Before? The isotope carbon-14 is used in radio- carbon-dating of animal and plant fossils. Uranium-238, uranium-235, and thorium-232 are isotopes that scientists use to tell the age of rocks and meteorites. BrainPOP Isotopes

Calculating the Mass of an Element Most elements found in nature contain a mixture of two or more stable (nonradioactive) isotopes The Atomic Mass is the average of the masses of all the naturally occurring isotopes of an element.

Lets try it! The metal thallium occurs naturally as 30 percent thallium-203 and 70 percent thallium-205. Calculate the atomic mass amu