The Atom Lesson 2 - Isotopes. Different Forms of the Same Element In any specific element, the # of protons is always constant. Unlike the number of protons,

Slides:



Advertisements
Similar presentations
4.3: HOW ATOMS DIFFER ATOMIC NUMBER
Advertisements

Atoms, Ions, and Isotopes. Quick Review Atoms are made up of three particles: Protons Neutrons Electrons Question: Which of the three particles identifies.
Chapter 11B Notes Determining Isotope Masses. Intro What is the mass of an atom with 6 protons and 6 neutrons? 12 What is the mass of an atom with 6 protons.
Atomic Mass & Number Isotopes The Periodic Table.
Atoms, Ions, and Isotopes. Quick Review Atoms are made up of three particles: Protons Neutrons Electrons Question: Which of the three particles identifies.
The Atom & the Periodic Table. Reading the Periodic Table.
Ch. 3 - Atomic Structure II. Masses of Atoms (p.75-80) Mass Number
Atomic Structure I. Subatomic Particles.
Atomic Mass. Isotopes Reminder Yesterday we learned that the mass of all atoms of a certain element are not always the same –Some atoms may have more.
Mass Number Atomic Number equals the # of... NUCLEUS ELECTRONS PROTONS NEUTRONS NEGATIVE CHARGE POSITIVE CHARGE NEUTRAL CHARGE ATOM.
4.2.
Determining the number of subatomic particles in an atom.
 Atoms of the same element with different numbers of neutrons.  What has changed if there is a different number of neutrons. HINT: look at your periodic.
Isotopes. Isotopes are atoms that have the same number of protons but different numbers of neutrons Most elements in the first two rows of the periodic.
Unit 2 Review - Section 1 Atomic Structure and Mass.
Average Atomic Mass.
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
 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.
Proton, Neutron, Electron Counting Protons (p + ) are positively charged and located in the nucleus The number of protons in each atom can be found on.
Ch. 3 - Atomic Structure II. Masses of Atoms (p.75-80)  Mass Number  Isotopes  Relative Atomic Mass  Average Atomic Mass.
Atomic Mass The Atomic Mass of Candium Lab. Atomic Mass This is the weighted average mass of the atoms in nature of that element A weighted avg mass reflects.
Atomic Mass. Masses in amu Only carbon-12 has an atomic mass exactly equal to its mass # One atomic mass unit (amu) is defined as 1/12 the mass of a carbon-12.
Isotopic Abundance SCH 3U. Atomic Mass The mass of an atom (protons, neutrons, electrons) Relative Atomic Mass: An element’s atomic mass relative to the.
Average atomic Mass. What does the atomic mass tell us on the Periodic table?
Average Atomic Mass. Relative Atomic Masses  Masses of atoms (in grams) are very small, so for convenience we use relative masses.  Carbon-12 is our.
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.
Notes on Isotopes Remember Protons are (+) and Electrons are (-). Neutrons were the last sub- atomic particles to be discovered because they have no electrical.
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.
Chapter 4 AVERAGE ATOMIC MASS. Atomic Mass… n The weighted average of the masses of all the naturally occurring isotopes of that element. n Is not a whole.
Notes on Isotopes Remember Protons are (+) and Electrons are (-). Neutrons were the last sub- atomic particles to be discovered because they have no electrical.
Chapter 3 Isotopes Part II. Atoms Nucleus is center core. Nucleus is center core. Nucleus is made of Protons & Neutrons. Nucleus is made of Protons &
Atomic Structure. Subatomic Particles In the nucleus: Protons Mass  1 amu Charge = +1 Neutrons Mass  1 amu Charge = 0 In the electron cloud: Electrons.
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.
ATOMS, IONS, AND ISOTOPES QUICK REVIEW Atoms are made up of three particles:  Protons  Neutrons  Electrons Question: Which of the three particles.
Unit 3 Atomic Structure and Periodicity. Dalton’s Atomic Theory 1.All matter is composed of _____________. 2. Atoms of the same element are _______________.
Starter In a neutral atom: the protons are equal to the electrons So how many electrons do the following elements have: Ne Sn Fe.
 Atoms  Elements are made of particles called atoms  Atoms are the smallest pieces of matter that contain all the properties of a specific element.
Do Now: Match the scientist with their contribution to the atom A. Dalton1. Mass of electron B. Thomson2. atomic theory C. Milikan3. discovered electron.
Lesson 24: Isotopes An element can be identified by the # of protons it has # of neutrons can vary Neutrons add to the mass of the atom, but do not change.
Calculating Atomic Mass
II. Masses of Atoms Mass Number
Calculating Average Mass
Isotopes.
Average atomic Mass.
The Atom Lesson 2 - Isotopes.
Ch Atomic Structure II. Masses of Atoms (p.30-31) Mass Number
Structure of the Nucleus – Outcomes
Unit 2: Atomic Theory & Structure
Lesson 13: Subatomic Heavyweights
Standard Atomic Weights on Periodic Table (red numbers) are found through the terrestrial (Sol III) relative abundances of the masses (in amu) of the isotopes.
The Atom Lesson 2 - Isotopes.
Mass of Individual Atoms
Isotopes QUICK NOTES Carbon-14
Elements, Isotopes and More
Isotopes Atoms with SAME number of PROTONS (atomic number) but DIFFERENT numbers of neutrons (i.e. mass number) 6 protons 6 neutrons 6 protons 7 neutrons.
How Atoms Differ Chp 4.
The Atom Lesson 2 - Isotopes.
Standard Atomic Weights on Periodic Table (red numbers) are found through the terrestrial (Sol III) relative abundances of the masses (in amu) of the isotopes.
Chemistry Unit: Chapter 3
Atomic Symbols = = mass # atomic # protons + neutrons protons
1. What are these two atoms of carbon called?
The Atom Unit 2 Topic 1.
The Atom Lesson 2 - Isotopes.
Atomic Structure Nucleons Atomic Number
Isotopes Atoms of the same element with a different number of neutrons
Ch. 4 - Atomic Structure II. Masses of Atoms Ch.4 Mass Number Isotopes
1. What are these two atoms of carbon called?
Find the average of the following numbers…
Section 2: Masses of Atoms
Presentation transcript:

The Atom Lesson 2 - Isotopes

Different Forms of the Same Element In any specific element, the # of protons is always constant. Unlike the number of protons, the number of electrons and neutrons can vary within atoms of an element without changing the identity of the element. Ex. Carbon (C) ALWAYS has 6 protons, but it can have anywhere from 6-8 neutrons and 2-10 electrons

Isotopes Isotopes are atoms of the same element (same number of protons) but with different number of neutrons Carbon has three isotopes Notice how the atomic # (# of protons) does NOT change but the mass number does.

Determining the mass number of isotopes The atomic mass on the periodic table is an average of all the known isotopes of each element. It is not the mass of any individual atom. To determine the mass number of a specific isotope you need to add the number of protons to the number of neutrons.

Practice A lithium atom has 3 protons, 3 electrons, and 3 neutrons. A = A nitrogen atom has 8 neutrons A = An unknown element has 92 protons and 143 neutrons. Element = A = U

Representing Isotopes Option # 1 U K C Option #2 U – 235 K - 40 C – 14 Only the mass number is listed, the atomic number can be found on the P.T

Finding average atomic mass To find the average atomic mass of an element you need two pieces of information: The mass numbers of the different isotopes Neon has three: Ne - 20, Ne - 21, Ne - 22 The relative abundance of each isotope Of all the neon measured, 90.60% is Ne-20, 0.200% is Ne-21, and 9.200% is Ne-22

Finding average atomic mass Even though it is the least massive, Ne- 20 accounts for the vast majority of Neon. IsotopeMassAbundanceMass Contribution Ne-2020 amu90.60%18.12 Ne-2121 amu0.20%0.042 Ne-2222 amu9.200%2.024 Avg. mass =20.19

Examples Gallium-69 has a relative abundance of 60.11% and Gallium-71 has a relative abundance of 39.89%. What is the average atomic mass of Gallium? Thallium has two stable isotopes, Thallium- 203 and Thallium-205. Thallium-203 has a relative abundance of 29.52%.Thallium-205 has a relative abundance of 70.48%. What is the average atomic mass of Thallium?