8th Chemistry - Atomic properties

St. George's College

8th CHEMISTRY Class:

Atomic Properties

Teacher's notes

Objectives

Vocabulary

April 6th

2009

Link and Learn

Prepared by

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8th Milton A ‐ Atomic Properties Name

Oral Intervention

Coin

Chocolate

Sergio María Fernanda Alejandra Almendra Anna Paula Sandra E‐C Maia María Belén Alfredo Kinley Arianne Sandra M. Fiorella Rodrigo Giulia Jaime Stefano Bruno

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8th Milton Alpha ‐ Atomic Properties Name

Oral Intervention

Coin

Chocolate

Marcelo Antonella Paulo Alejandro Brenda Diego Gabriel Valeria Cristina Giuliana Joshua María Gracia Gonzalo N. Paolo Gonzalo R. Giorgio Nicolás María Claudia

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ATOMIC PROPERTIES

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ATOMIC NUMBER • Each element has an Atomic Number, and is determined by the number of protons.

• All the atoms of a particular element have the same number of protons.

Atomic Number = Number of Protons

MASS NUMBER • The mass of each element is determined by the number of protons and neutrons.

• The mass of electrons is so minute that it is not considered in the calculations of the atomic mass.

Atomic Mass = Number of Protons + Number of Neutrons 5

ISOTOPES • Some elements are made up of atoms with different masses.

• For atomic masses, the number of protons always remains the same.

• Isotopes are atoms of the same element, with the same number of protons nut with a different number of neutrons. e‐

e‐

e

e‐

‐

e‐

e‐

e

e‐

‐

e‐

e‐

e‐

e‐

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The Nuclei of the three isotopes of Hydrogen Protium

Tritium

+

+

1 proton

1 proton 1 neutron

Deuterium

+ 1 proton 2 neutrons

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Carbon 14 • Cosmic rays, containing high levels of energy (ultraviolet light), break apart the atoms in the atmosphere, causing neutrons to fly apart and collide with other atoms (troposphere).

• When these neutron collide with the most common gas in 14 the atmosphere (Nitrogen), a proton is expelled and N 7 14 C becomes .

7 • Isotopes are chemically similar but physically different.

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NEUTRON DECAYS INTO PROTON PLUS ELECTRON

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INVESTIGATION

E‐Portfolio • Investigate the techniques used to date remains found from the past.

• This publication must contain 100 words as a minimum, and 150 words maximum.

• You can use other resources to complement your publication, such as: audio, video, animations, etc.

• Just remember: CITE your SOURCES of INFORMATION, and USE YOUR OWN WORDS.

Click below for the easy way

Click below for the right way

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ISOBARS • Formed by groups of atoms with different atomic number but with the same atomic mass.

• Isobars are chemically different but physically similar.

• Examples: 40 20

Ca

40 18

Ar

ISOTONES • Isotones are elements that have the same number of neutrons.

• Example: 17p+ + 20n0 = 37

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19p+ + 20n0 = 39 19

Cl

K 13

ISOMERES • Formed by compounds with the same formula but different molecular structures.

C6H12O6 Inositol

Hexoses

9 others Fructose

Glucose

Galactose

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Exercise 1 Complete the following table in the shortest time possible and present it for 1 extra point in the following test.

Element's Name

Chemical Symbol

Atomic Number

Os

Atomic Mass

# Electrons

190 65

Curium

30

247 Hg 43

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Exercise 2 Calculate the molecular mass in the following compounds: Carbon Dioxide Water Carbon Monoxide Sodium Chloride Hydrogen Peroxide

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Exercise 3 1. What is the percentage by mass of oxygen (O) in sodium hydroxide (NaOH)?

2. What is the percentage by mass of chlorine (Cl) in perchloric acid (HClO4)?

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Teacher's Notes This class has been designed to cover the topics of Atomic Properties for the week of Monday April 6th till Wednesday April 8th.

For further knowledge about this topic: 1. Conduct a thorough search under the topic: Atomic Properties on the Web, books and magazines.

2. If findings are not specific, ask your teacher for suggestions.

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Objectives • Describe the properties of elements in terms of atomic numbers, and atomic masses.

• Identify elements by chemical symbol, atomic number and atomic mass.

Note: All, or most, of the objectives will be covered during class time, however the student must be responsible for those objectives not covered or concluded.

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Vocabulary • Atom: the smallest unit of an element that still has the properties of that element.

• Proton: a subatomic particle that has positive electric charge.

• Nucleus: the control center of a cell that directs the cell's activities. The center of an atom, usually made of protons and neutrons.

• Neutron: a subatomic particle that has the same mass as a proton but no electric charge.

• Electron: a subatomic particle that orbits an atom's nucleus, has a negative electric charge, and has very little mass.

• Atomic Number: the number of protons in an atom.

• Element: a substance made up of only one kind of element.

• Metal: a substance that conducts heat and electricity well and is malleable.

• Nonmetal: a substance that does not conduct electricity and is not malleable.

• Proton: a subatomic particle that has a positive electric charge.

• Periodic Table: a table that shows the elements arranged by their atomic numbers.

• Compound: a substance made up of atoms of two or more elements that are chemically combined.

• Melting Point: the temperature at which a substance changes from a solid to a liquid.

• Boiling Point: the temperature at which a substance changes from a liquid to a gas.

• Plasma: a state of matter made up of charged atoms, uncharged atoms, and free electrons.

Note: Most of the vocabulary words will be covered during class time, however the student must be responsible for those words not covered or concluded.

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Link and Learn You can visit the following websites to improve your understanding on the present topic: • • • • •

http://www.creation‐science‐prophecy.com/C14a.htm http://science‐learning2009.wikispaces.com http://learningandscience.blogspot.com www.sanjorge.edu.pe http://libraryatstgeorges.blogspot.com

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Resources Used Slide

Resource

Description

Origin

G1 ‐ 2 Image

John Milton

http://bit.ly/QAYb

G1 ‐ 4 Image

Atoms

http://bit.ly/BqTh

G1 ‐ 7 Images

Helium Isotopes Carbon 14 Isotopes

http://bit.ly/Hhz7Z http://bit.ly/10rlfM

G1 ‐ 8 Image

Carbon 14 formation

http://bit.ly/MSA0V

G1 ‐ 9 Animation Periodic Table

Notebook Gallery

G1 ‐ 10 Images

Carbon ‐ Nitrogen reaction http://bit.ly/MSA0V http://bit.ly/2pNa39 Beta decay 1 http://bit.ly/13Rciv Beta decay 2

G1 ‐ 11 Images

Carbon 14 to Nitrogen 14‐1 http://bit.ly/h7Cxr Carbon 14 to Nitrogen 14‐2

E‐Portfolio G1 ‐ 12 Images Animation Puzzle pieces Copy and Paste Idea

http://bit.ly/W7ccA http://bit.ly/Dbbtf http://bit.ly/2ZxTj Notebook Gallery

G1 ‐ 14 Image

http://bit.ly/OPIoM

Glucose

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Prepared by

Gerardo LAZARO Science Lead Teacher Email: glazaro@sanjorge.edu.pe Wiki: http://science‐learning2009.wikispaces.com Blog: http://learningandscience.blogspot.com Twitter: http://twitter.com/glazaro

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