Atomic Mass and Isotopes. Review Quiz ParticleChargeMassLocationSymbol Electron Proton Neutron.

Slides:

Advertisements

Similar presentations

Reviewing Subatomic Particles

Advertisements

4.3: HOW ATOMS DIFFER ATOMIC NUMBER

Average Atomic Mass. How much does an atom weigh?  Protons & Neutrons:  1.67 X gram  Electrons:  9.10 X gram  To avoid working with.

Chemistry chapter 3 Sample Problems. Isotopes The number of neutrons is found by subtracting the atomic number from the mass number. Mass # (235)---atomic.

AIM: HOW TO CALCULATE THE AVERAGE ATOMIC MASS? DO NOW:1. WHAT ARE THE 3 SUBATOMIC PARTICLES OF AN ATOM? LIST THE THREE SUBATOMIC PARTICLES AND THEIR CHARGE.

Atomic Number What makes one element different from another? 4.3

Atomic Structure Nucleus – contains protons and neutrons

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.

OF PROTONS, NEUTRONS AND ELECTRONS IN AN ATOM

Atoms: The building blocks of Matter

Atomic Structure. Subatomic Particles (Particles that make up an atom) ● Proton (p+) - Positively charged - Found in the nucleus - Large mass ●Neutron.

Bell work  1. Which subatomic particles reside in the nucleus?  2. If we are looking at Carbon-14, how many protons, electrons, and neutrons are present.

Isotopes and Mass Number. Atomic Number The number of protons in each atom identifies it as an atom of a particular element Each atom has a unique number.

Bellringer 10/01/12 How many protons, neutrons and electrons are in U-235 and Pu-244?

Counting Atoms.

Section 3 Counting Atoms Lesson Starter Imagine that your semester grade depends 60% on exam scores and 40% on laboratory explorations. Your exam scores.

Atomic Structure I. Subatomic Particles.

Distinguishing Among Atoms

Mass Number Atomic Number equals the # of... NUCLEUS ELECTRONS PROTONS NEUTRONS NEGATIVE CHARGE POSITIVE CHARGE NEUTRAL CHARGE ATOM.

Isotopes Atoms of the same element that different mass numbers

Unit 3: Atomic Theory & Structure Section 2 – Distinguishing Among Atoms.

THE ATOM Counting. The Atom  Objectives Explain what isotopes are Define atomic number and mass number, and describe how they apply to isotopes Given.

Average Atomic Mass The weighted average of the masses of all the naturally occurring isotopes of an element.

Isotopes As techniques for finding the masses of atoms has improved, we have learned that not all atoms of the same element are identical. Isotopes – atoms.

Chapter 3 Atoms: The Building Blocks of Matter. The Atomic Theory  Law of conservation of mass  Mass is neither destroyed nor created  Law of definite.

Unit 2 Review - Section 1 Atomic Structure and Mass.

Counting Atoms 3.3. Counting Atoms Very difficult to count Atomic Number – # of p + of each atom of that element Whole numbers Elements arranged by atomic.

More about isotopes Atomic mass vs average atomic mass or atomic weight.

& Average Atomic Mass  Atoms with the same number of protons (they are the same element) but different number of neutrons.

 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.

Subatomic Particles. Atomic Particles ParticleChargeMass (kg)Location Electron9.109 x Electron cloud Proton x Nucleus Neutron

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.

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.

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.

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.

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.

Chapter 3 Average Atomic Mass. Section 3 Counting Atoms Relative Atomic Masses The standard used by scientists to compare units of atomic mass is 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.

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.

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.

How Atoms Differ. a. Properties of Subatomic Particles ParticleSymbolLocationRelative Charge Relative mass Actual mass (g) Electron Proton Neutron.

Chapter 3 Preview Lesson Starter Objectives Atomic Number Isotopes

Protons, Neutrons, and Electrons

Chemistry.  Atomic Number  Mass Number  Isotopes  Atomic mass unit  Atomic mass.

Atomic Structure. Subatomic Particles In the nucleus: Protons Mass  1 amu Charge = +1 Neutrons Mass  1 amu Charge = 0 In the electron cloud: Electrons.

Atomic Structure Chapter 4. Sizing up the Atom O Radii of most atoms: 5 x m to 2 x m O Copper penny contains 2.4 x atoms. The population.

The Mole Continued.  The mole is also defined as the number of protons in g of protons.

This is the solution for carbon: (12) (0.9890) + (13) (0.0110) = amu mass number percent abundance % % Recall!!! carbon:

Average Atomic Mass!!!. Copper is made of two isotopes. Copper- 63 is 69.17% abundant and it has a mass of amu. Copper-65 is 30.83% abundant and.

Concept Check 2.1 Atomic Size

1 The Atom Atomic Number and Mass Number Isotopes.

Same Element Different Atom- Isotopes All atoms of a particular element are not exactly alike. Some elements have atoms with different masses (isotopes)

Do Now: Match the scientist with their contribution to the atom A. Dalton1. Mass of electron B. Thomson2. atomic theory C. Milikan3. discovered electron.

LecturePLUS Timberlake1 Atoms and Elements The Atom Atomic Number/Mass Number/ Isotopes.

ATOMIC STRUCTURE THE NUCLEUS: 1) THE PROTON:

Calculating Atomic Mass

Average Atomic Mass In nature, most elements are a mixture of different isotopes The mass of a sample of an element is a weighted average of all the isotopes.

Calculating Average Mass

ATOMIC STRUCTURE THE NUCLEUS: 1) THE PROTON:

Section 3 Counting Atoms

Chapter 3 Table of Contents

Mass of Individual Atoms

Isotope -an atom with a different number of NEUTRONS than protons.

Elements, Isotopes and More

Calculating Average Atomic Mass

Atomic Math Calculations

Atomic Number and Mass Number

Presentation transcript:

Atomic Mass and Isotopes

Review Quiz ParticleChargeMassLocationSymbol Electron Proton Neutron

HW Review 2.1 How did Thomson’s view of the atom differ from that of Democritus? 2.2 When alpha particles are shot at a thin gold leaf, only one particle in about 20,000 bounces back. How would Rutherford explain this observation?

HW Review 2.3 What is the atomic number of a neutral atom that contains 14 electrons? Explain. 2.4 A certain atom contains 6 protons, 8 neutrons, and 6 electrons. How many and which of these particles are in the nucleus of the atom?

Isotopes Same # of p +, different # of n 0 Same element, different mass Same element, different mass #

EXAMPLE OF AN ISOTOPE Cl Cl NEUTRONS ATOMIC MASS 18 NEUTRONS ATOMIC NUMBER

Finding Atomic Mass Weighted average of the naturally occurring isotopes If 75.4% of chlorine atoms have a mass of 35 amu, and 24.6% have a mass of 37 amu, calculate the mass of an average Cl atom. Multiply the mass by the abundance in decimal form, then add. 35 amu X.754 = amu X.246 = amu

Problem 69% of copper atoms weigh 63 amu. 31% weigh 66 amu. What is the average? 63 X.69 = X.31 = amu

Problem Silver has two isotopes, Ag has a mass of amu ( 52.00% ), and Ag has a mass of amu (48.00%). What is the atomic mass of silver? X.52 = X.48 = Answer:

Gram-Atomic Mass Gram-atomic mass of an element is the atomic mass expressed in grams. When using moles, just change amu to grams 1 atom of 12 C = 12 g 1 mole 12 C = 12 g 1 mol carbon = 1 mol copper = g 63.5g

Gram-atomic mass How do you compute the mass of a single atom? Sodium (Na) gram-atomic mass = 23.0g # of atoms in any element’s gram-atomic mass = 6.02 X grams 6.02 X atoms = 3.82 X gram/atom

Review Problem