Isotopes and Average Atomic Mass. Scientists have discovered that each element consists of atoms that are virtually identical. There is a notable exception,

Slides:



Advertisements
Similar presentations
4.3: HOW ATOMS DIFFER ATOMIC NUMBER
Advertisements

Atomic Number, Mass Number, Atomic Mass and Isotopes Mrs. Coyle Chemistry.
Atomic Structure Nucleus – contains protons and neutrons
Atomic Mass & Number Isotopes The Periodic Table.
Isotopes Chemistry.
ISOTOPES Chemistry. Isotope Definition: A different form of an element. Proton number is the same as the other forms or isotopes. Electron number is the.
The Atom & the Periodic Table. Reading the Periodic Table.
 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.
Reading the Periodic Table. The top number is the atomic number or the number of ______________________ Cl is an abbreviation for ______________________.
Isotopes Atoms of the same element that different mass numbers
4.2.
The Atom.
The Atomic Number. Reminder: Elements are different types of atoms (like different LEGO blocks) Elements are defined by the number of protons in the nucleus.
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 
More about isotopes Atomic mass vs average atomic mass or atomic weight.
Masses of Atoms. Atomic Mass  Remember that Protons and Neutrons are much bigger than an Electron.  Because of this, the nucleus contains the majority.
 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.
Section 4.3 How Atoms Differ. Objectives Explain the role of atomic number in determining the identity of an atom Define an isotope and explain why atomic.
Review!!! A neutral atom has an Atomic Number of 82 and a Mass Number of 207. What is this element? How many protons? How many electrons? How many neutrons?
Chapter 4.3 Distinguishing Among Atoms
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. Relative Atomic Masses  Masses of atoms (in grams) are very small, so for convenience we use relative masses.  Carbon-12 is our.
Atomic Number & Atomic Mass
Atomic Masses Test Friday!. Atomic Mass is an average (decimal) An average of known isotopes for an element The atomic mass of an element is closest to.
PS-2.2 Illustrate the fact that the atoms of elements exist as stable or unstable isotopes.
Notes on Isotopes Remember Protons are (+) and Electrons are (-). Neutrons were the last sub- atomic particles to be discovered because they have no electrical.
The Nuclear Atom Atoms differ from one another by their number of: 1.Protons 2.Neutrons 3.Electrons Electrons have a NEGATIVE charge. The MASS of an electron.
Parts of the Atom: Properties  Protons: –Positive charge –Located in nucleus –Mass = 1 amu (Atomic Mass Unit)  Neutrons –No charge (neutral) –Inside.
Notes on Isotopes Remember Protons are (+) and Electrons are (-). Neutrons were the last sub- atomic particles to be discovered because they have no electrical.
Isotopes & Ions 4.7; Subatomic Particles Remember Dalton?  Remember Dalton’s atomic theory?  “All atoms of a given element are identical”. 
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.
Topics Subatomic Particles, their Mass & Electric Charge Protons Neutrons Electrons Atomic Number Isotopes Atomic Mass Molar Mass Average Atomic Mass Calculating.
Atomic notation X A Z X = Symbol (C, Au) A = Atomic Mass Number = #nucleons (Protons + Neutrons) Z = Atomic Number = #protons C 12 6 Carbon A = 12, Z =
Atomic Structure - Bellwork What experiment did Rutherford perform that identified positively charged nucleii in an atom? What do we call Thomson’s atomic.
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.
Isotopes. What is an isotope? Not all atoms of an element are identical. Some elements have isotopes. Isotopes (iso means “same”) are atoms with the same.
{ Atom and Isotope Review Physical Science. An atom has 6 protons, 8 neutrons, and 6 electrons. What is the atomic mass?
Essential Question: How do atoms of the same element differ?
3.00_Chemistry of Biology Biology I (Isotopes)
Masses of Atoms.
Warm-up: Complete the following table
Atomic Structure and Isotopes
ISOTOPES.
Atomic Structure Concepts.
Isotopes.
A B 21085At Fe Mo 5827Co 3216S Pb4+ Symbol
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 Walk Around
Distinguishing Between Atoms
How do structures of atoms Differ?
Lesson 13: Subatomic Heavyweights
Ch. 4/5 Notes Day 3 1/28/16.
Isotopes - isotope: atoms of the same element that have different numbers of neutrons - Carbon, as found in nature, is a mixture of isotopes, including.
Atomic Structure Chemistry.
Section 1 Structure of the atom and cells on the periodic table
Foldables: Atoms Terms.
Title: Atomic Properties
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.
Atomic Structure Chemistry.
Atomic Structure Isotope
How We Know What We Can’t See Looks Like Day 4 Average Atomic Mass
Atomic Structure Protons- positively charged, found in nucleus
Atomic Structure Nucleons Atomic Number
Isotopes.
Atomic Number, Mass Number, Atomic Mass and Isotopes
Atomic Math Calculations
How We Know What We Can’t See Looks Like Day 4 Average Atomic Mass
Chemistry Chapter 3 Section 3
Presentation transcript:

Isotopes and Average Atomic Mass

Scientists have discovered that each element consists of atoms that are virtually identical. There is a notable exception, however. While the element carbon is defined as being made up of neutral atoms with 6 protons and 6 electrons, not every carbon atom has the same number of neutrons. Carbon has three naturally occurring isotopes.

What are Isotopes? O Atoms of the same element that have different numbers of neutrons (same # of electrons and protons), therefore, different mass numbers (atomic mass).

How many isotopes can an element have? O All elements have a number of isotopes. Hydrogen has the fewest number of isotopes with only three. The elements with the most isotopes are cesium and xenon with 36 known isotopes.

Stable and Unstable Isotopes O Some isotopes are stable and some are unstable. O When an isotope is unstable it will decay over time and eventually it will turn into another isotope or element. O Unstable isotopes are considered radioactive. Most elements that are found in nature are made up of stable isotopes. O The element with the most stable isotopes is tin which has ten different stable isotopes.

Writing a symbol for an Isotopes?

Calculating Average Atomic Mass

Calculating average atomic mass In order to determine the atomic weight of an element accurately, the atomic masses of the isotopes and the percentage of each isotope must be arrived at experimentally, and calculated.

Calculating Average Atomic Mass

Example # 1