PowerPoints II-9 to III-16. De La Salle High School Mr. Puccetti

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PowerPoints II-9 to III-16 De La Salle High School Mr. Puccetti

II-9 ChemCatalyst Create a Table Properties of the Elements HW#1 (42): 1-3 Lab Report due Friday 1. What patterns do you see in how the elements are organized? 2. What do the numbers represent?

Create a Table Properties of the Elements How did Mendeleyev organize the elements into the periodic table?

Create a Table Properties of the Elements II-9 Notes Periodic Table of the elements: An organization of the elements in rows ( ) and columns ( )

Create a Table Properties of the Elements II-9 Notes Atomic mass: A measure of the relative mass of an element Atomic mass units: The units used for atomic mass (amu).

Create a Table Properties of the Elements II-9 Notes Properties: The properties of elements include color, hardness, and reactivity. Iodine I 2 Sodium Na Sulfur S

Create a Table Properties of the Elements II-9 Notes Reactivity: The reactivity of an element is related to whether or not it will combine with other substances as well as the speed with which the products form. Iodine I 2 Sodium Na Sulfur S

Which of the following elements belong in a group? II-9 Check- In Cadmium Cd Moderately soft, silvery solid, metal React very slowly with water Found in CdCl 2 (s) Zinc Zn Moderately hard, silvery solid, metal Reacts very slowly with water Found in ZnCl 2 (s) Iodine I Purple solid, nonmetal Reacts slowly with metals Found in ICl (s) Mercury Hg Silvery liquid, metal Does not react with water Found in HgCl 2 (s)

II-10 ChemCatalyst Breaking the Code The Periodic Table Look at the periodic table poster. Where would you put copper on the periodic table? Explain your reasoning. Copper shiny, reddish metal HW#2 (50): 1, 2, 4-7 & Color Code your Periodic Table (instructions on webpage) Cu 63.5 Reacts slowly with oxygen Found in CuCl

HW#2 (50): 1, 2, 4-7 & Color Code your Periodic Table (instructions on webpage) Breaking the Code The Periodic Table Copper Cu 63.5 shiny, reddish metal Found in CuCl

Breaking the Code The Periodic Table Where did Mendeleyev put copper (Cu) in his periodic table?

Mendeleyev s table has ten elements like copper, with atomic masses between 40.1 and 69.7 Breaking the Code The Periodic Table

Breaking the Code The Periodic Table The periodic table opens up to make room for more elements

Breaking the Code The Periodic Table Then add Mendeleyev s remaining elements -- keeping them in their columns

Breaking the Code The Periodic Table The Modern Periodic Table

Breaking the Code The Periodic Table What information does the periodic table reveal about the elements?

Breaking the Code The Periodic Table What information does the periodic table reveal about the elements?

Key: Groups ( ) Periods ( ) Breaking the Code The Periodic Table

Breaking the Code The Periodic Table Groups ( ): Elements in a group have similar properties. They are arranged in vertical columns on the periodic table Key: Groups ( ) Periods ( ) I II III IV V VI VII VIII

Breaking the Code The Periodic Table Periods: The horizontal rows on the table. The patterns repeat over and over again at the start of each new row. Key: Groups ( ) Periods ( ) 1 2 3 4 5 6 7

Breaking the Code The Periodic Table II-10 Check-in List 5 things to describe the element silver (Ag). Copper shiny, reddish metal Gold shiny, yellow metal Cu Au 63.5 197.0 Reacts slowly with oxygen Found in CuCl not very reactive Found in AuCl

Breaking the Code The Periodic Table Use pens and/or colored pencils to label the following on your periodic table (make a key): groups (columns), periods (rows), metals, non-metals, gases, halogens, alkali metals, alkaline metals, noble gases, transition elements, metalloids Mark the 2 most reactive elements on your periodic table with a. Hint: One element is a metal and the other is a non-metal. HW#2 (50): 1, 2, 4-7 & Color Code your Periodic Table (instructions on webpage)

09/7/09: Atomic Pudding Models of the Atom HW#3 (57): 1-4 III-11 ChemCatalyst 0.00000000041 meters The drawing is a model of a very tiny cube of gold. 1. What does the model tell you about the element gold? What do the spheres represent? What are atoms? 2. How would you draw copper to show that it is different from gold? Explain your reasoning.

Atomic Pudding Models of the Atom Atoms: Extremely small particles, which cannot be seen. All matter is made up of atoms. III- 11 Note s Models: A simplified representation of something more complex, that facilitates understanding certain aspects of a real object or process.

Atomic Pudding Models of the Atom How are the smallest bits of matter described? III- 11 Note s In 1803, John Dalton proposed that atoms were simply solid spheres. In the decades that followed chemists collected a lot of evidence suggesting that there was more to the atom.

Atomic Pudding Models of the Atom How are the smallest bits of matter described? This lesson will introduce you to various models for the atom that have appeared over the past two hundred years. The descriptions of five models of the atom are on a separate handout.

The Progression of Models Solid Sphere Model Plum Pudding Model Nuclear Model Dalton, 1803 Thomson, 1897 Rutherford 1911 Solar System Model Bohr, 1913 Proton Model Rutherford, 1918

Atomic Pudding Models of the Atom III- 11 Note s Models S tructures Solid Sphere Model (Dalton, 1803) None a solid sphere Plum Pudding Model (Thomson, 1897) Electrons nega tive charge Fluid positive charge

Atomic Pudding Models of the Atom III-11 Notes Models S tructures Nuclear Model (Rutherford, 1911) Electrons nega tive charge Nucleus positive charge Electrons circle around the nucleus Solar System Mo del (Bohr, 1913) Electrons nega tive charge Nucleus positive charge Electron orbits at different distances from the nucleus Proton Model (Rutherford, 1918) Electrons nega tive charge Protons positive charge Nucleus of protons. Electrons circle around the nucleus

Atomic Pudding Models of the Atom III-11 Notes Model of the Atom electrons protons and neutrons in the nucleus Atoms: Extremely small particles, which cannot be seen. All matter is made up of atoms.

09/10/09 III-12 : Atoms By Numbers Atomic Number & Atomic Mass (1) III-11 ChemCatalyst HW#4 see board 1. Label the following diagram 2. What are the charges associated with each of these particles? (2) and (3) are in the nucleus Helium, He 3. List 3 similarities and 3 differences between the atomic models of He and Be. 4. Why do you think helium is #2 (the second element), and beryllium is #4 on the periodic table? Beryllium, Be

Atomic Pudding Models of the Atom III-11 Notes Model of the Atom Electrons (-) Protons (+) and neutrons (ø) in the nucleus The atom is composed of even smaller pieces called protons, neutrons, and electrons.

Atomic Pudding Models of the Atom III-11 Notes Model of the Atom electrons protons and neutrons in the nucleus The protons and neutrons are located in the dense nucleus of the atom. The electrons surround the nucleus.

Atomic Pudding Models of the Atom III-11 Notes Model of the Atom Electrons (-) Protons are positive (+). Neutrons are neutral (Ø). Electrons are negative (-). Atoms are neutral (Ø). The nucleus or an atom is positive (+). Protons (+) and neutrons (ø) in the nucleus

09/10/09 III-12 : Atoms By Numbers Atomic Number & Atomic Mass (1) 1. Label the following diagram 2. What are the charges associated with each of these particles? III-11 ChemCatalyst HW#4 see board (2) and (3) are in the nucleus Helium, He 3. List 3 similarities and 3 differences between the atomic models of He and Be. 4. Why do you think helium is #2 (the second element), and beryllium is #4 on the periodic table? Beryllium, Be

Atoms By Numbers Atomic Number and Atomic Mass III-12 Notes How are the atoms of one element different than the atoms of another element? Helium, He Berylium, Be

Atoms By Numbers Atomic Number and Atomic Mass III-12 Notes Atomic number is the number of protons in the nucleus of an atom. Atomic number = # protons Henry Mosely If you change the proton number, you change the element.

Atoms By Numbers Atomic Number and Atomic Mass III-12 Notes The atom is neutral so # protons (+) = # of electrons (-) electrons protons and neutrons in the nucleus Atomic number = # protons = # of electrons

Atoms By Numbers Atomic Number and Atomic Mass III-12 Notes The proton and neutron account for most of the mass in an atom.

Atoms By Numbers Atomic Number and Atomic Mass Atomic mass of an atom: The mass of an atom in amu s is approximately equal to the number of protons + the number of neutrons. protons and neutrons in the nucleus The mass of an atom is measured in amu (atomic mass units) Mass of one proton = 1 amu. Mass of one neutron = 1 amu. Mass of one electron = ~0.0005 amu (very tiny)

Atoms By Numbers Atomic Number and Atomic Mass The proton and neutron account for most of the mass in an atom. Atomic mass = protons + neutrons electrons protons and neutrons in the nucleus

Atoms By Numbers Atomic Number and Atomic Mass Atomic mass of an atom: The mass of an atom in amu is approximately equal to the number of protons added to the number of neutrons. Atomic mass = protons + neutrons electrons protons and neutrons in the nucleus To find neutrons: neutrons = Atomic mass (rounded to the nearest whole #) atomic number (protons)

Atoms By Numbers Atomic Number and Atomic Mass Symbols associated with elements Atomic number Atomic mass C 6 12.01 5 B 10.8 Element Symbol C B

Atoms By Numbers Atomic Number and Atomic Mass Symbols associated with elements III- 12 Note s Atomic number Atomic mass C 6 12.01 5 B 10.8 Atomic number = # protons = # of electrons Atomic mass = # protons + # neutrons # of neutrons?

Atoms By Numbers Atomic Number and Atomic Mass Each successive element in the periodic table has one more proton than the element preceding it. The atomic number of an atom is equal to the number of protons in its nucleus. The number of electrons in an atom is equal to the number of protons because an atom is neutral. The mass of a proton is 1 atomic mass unit or 1 amu. The mass of a neutron is also 1 amu. The atomic mass of an atom in amu is just the sum of the number of protons and neutrons. How are the atoms of one element different than the atoms of another element? The mass of the atom is found in the nucleus.

Atoms By Numbers Atomic Number and Atomic Mass III- 12 Note s Use your periodic table to identify the following elements: a) Atomic number 18 b) Has three electrons c) Atomic mass of 16.0

Subatomic Heavyweights Isotopes III- 13 Note s 1. What is different about the two atoms? 2. What is the atomic mass/atomic number of each atom? 3. Do you think they are both Lithium atoms? Why or why not?

N P Subatomic Heavyweights Isotopes How can atoms of the same atom differ? III- 13 Note s Protons = Neutrons = Electrons = Protons = Neutrons = Electrons =

Subatomic Heavyweights Isotopes How can atoms of the same atom differ? III- 13 Note s Protons = (6) same Neutrons = (6) Different Electrons = (6) same? Protons = (6) same Neutrons = (7) Different Electrons = 6 same?

Subatomic Heavyweights Isotopes III- 13 Note s Isotope: Atoms of the same element that have different numbers of neutrons. Protons = same Neutrons = Different Electrons = same Protons = same Neutrons = Different Electrons = same

Subatomic Heavyweights Isotopes III-13 Notes Isotopes: Atoms of the same element that have different numbers of neutrons Isotopes have the same number of protons and electrons but different numbers of neutrons. 3 Protons 3 Neutrons 3 Electrons 3 Protons 4 Neutrons 3 Electrons

Subatomic Heavyweights Isotopes III- 13 Note s The atomic mass of the element is the average of the masses of the atoms in the sample. Compared to the definition of the atomic mass of an atom Atomic mass of an atom: The mass of an atom in amu is approximately equal to the number of protons added to the number of neutrons. Atomic mass = protons + neutrons

Subatomic Heavyweights Isotopes III-13 Notes Atomic mass of an atom of Ne = 20, 21, or 22 Atomic mass of Ne = 20.18 amu

Subatomic Heavyweights Isotopes III-13 Notes What is the average atomic mass of Ne? 90% of atoms weigh 20 amu 1% of Ne atoms weigh 21 amu 9% of atoms weigh 22 amu

Subatomic Heavyweights Isotopes III-13 Notes What is the average atomic mass of Ne? 90% of atoms weigh 20 amu 1% of Ne atoms weigh 21 amu 9% of atoms weigh 22 amu

Subatomic Heavyweights Isotopes III-13 Wrap Up Notes The atomic weight of an element listed on the periodic table is the average mass of the naturally occurring isotopes of that element.

Isotopia Stable and Radioactive Isotopes III-14 ChemCatalyst Predict the isotopes of carbon, C. Which isotope is more abundant? How do you know? C 6 12.01

Subatomic Heavyweights Isotopes 5 B 10.8 P N

Subatomic Heavyweights Isotopes III-13 Notes Isotope Symbols Atomic Number Atomic Mass 5 B 10.8 10 5 B Boron-10 11 5 B Boron-11

Subatomic Heavyweights Isotopes III-13 Notes Atomic Mass Atomic Number Chemical Name- Atomic Mass Isotope Symbols 10 5 B Boron-10 5 B 10.8

Subatomic Heavyweights Isotopes III-13 Notes Isotope Symbols Atomic Mass AM = p + n Atomic Number AN = # p Chemical Name- Atomic Mass AM AN Sy Symbol-AM

Subatomic Heavyweights Isotopes III-13 Wrap Up- Notes Isotopes are referred to by their mass numbers (not the neutron #). Example: boron-10 and boron-11 10 B 11 B 5 5 Boron-10 Boron-11

Subatomic Heavyweights Isotopes III-13 Notes What types of isotopes do various elements have? 6 Li Li 3 3 Lithium-6 Lithium-7 7

Subatomic Heavyweights Isotopes III-13 Notes Isotopes have the same number of protons and electrons but different numbers of neutrons. The atomic weight of an element listed on the periodic table is the average mass of the naturally occurring isotopes of that element. Isotopes are referred to by their mass numbers. (example: boron-10 and boron-11)

Isotopia Stable and Radioactive Isotopes III-14 ChemCatalyst Predict the isotopes of carbon, C. Which isotope is more abundant? How do you know? C 6 12.01

Isotopia Stable and Radioactive Isotopes

Chart of Naturally Occurring Isotopes In Textbook

Isotopia Stable and Radioactive Isotopes Atoms must have at least one neutron for every proton in the nucleus (with the exception of hydrogen).

Isotopia Stable and Radioactive Isotopes Many isotopes have more neutrons than protons. The larger an atom is the more neutrons it needs in the nucleus to be stable.

Isotopia Stable and Radioactive Isotopes Radioactivity Radioactive isotope: Any isotope that has an unstable nucleus and breaks apart or decays over time. Compared to... Stable isotope: An isotope that does not break apart into smaller atoms.

Isotopia Stable and Radioactive Isotopes III-14 Wrap-up What types of isotopes do various elements have? There are somewhere between 1 and 10 isotopes of each element found in nature. The neutron to proton ratio is an important factor in determining the stability of a nucleus. Some elements have isotopes that are radioactive. The nuclei of radioactive isotopes are unstable and they break apart over time producing atoms with smaller masses.

III-15: Nuclear Quest Nuclear Reactions

Chem Catalyst Stable and Radioactive Isotopes Which of the following are isotopes of copper? Explain your reasoning. 63 Cu 197 Au 63 Cu 87 Cu 34 Cu 65 Cu 29 79 28 29 29 29

Alpha Decay III-15 Notes Alpha decay: A nuclear reaction in which an atom emits an alpha particle. Its atomic number decreases by 2, and its mass number decreases by 4.

Beta Decay III-15 Notes Beta decay: A nuclear reaction in which a neutron changes into a proton, and the atom emits a beta particle. The atom s atomic number increases by 1.

III-15: Nuclear Quest Nuclear Reactions III-15 Notes Nuclear chemistry is the study of changes to the nucleus. Nuclear reaction: A process that involves changes to the nucleus of an atom. Radioactive decay: A spontaneous process by which an atom emits radiation or a particle from its nucleus to become more stable. Fusion: The joining of two nuclei to form a larger nucleus accompanied by a release of energy. Fission: The splitting apart of an atomic nucleus into two smaller nuclei accompanied by a release of energy.

ChemCatalyst 09/15/09 1. What patterns do you notice in the fusion reactions? 2. Do you think gold can be created on Earth by a fusion reaction? Explain your thinking.

III-15: Nuclear Quest Nuclear Reactions III-15 Wrap- Up Changes in the nucleus of an atom can change the identity of an element. Alpha particle: A particle composed of two protons and two neutrons, equivalent to the nucleus of a helium atom. Beta particle: An electron emitted from the nucleus of an atom during beta decay. Gamma ray: A form of high-energy electromagnetic radiation emitted during nuclear reactions.

III-15: Nuclear Quest Nuclear Reactions III-15 Wrap- Up What are nuclear reactions? Alpha decay results in a in the atomic number by. results in an increase in the atomic number by. Gamma radiation usually accompanies alpha and beta decay and also fission. Gamma radiation can be quite harmful to humans.

III-15: Nuclear Quest Nuclear Reactions III-15 Wrap- Up Nuclear fission involves a single nucleus breaking apart into two smaller nuclei. Nuclear fusion involves two nuclei combining to form a nucleus with a larger atomic number. Nuclear fusion takes place in extremely hot environments, such as the cores of stars.

III-16: Old Gold Formation of Elements How are new elements formed? Radioactive decay, nuclear fusion, and nuclear fission are all nuclear processes that result in the creation of new elements. The mass of a nucleus changes when neutrons or protons are added or lost. The identity of an element changes when its nucleus gains or loses protons.

Check-In Write the nuclear equation showing technetium-100 undergoing alpha decay. Write the nuclear equation showing barium undergoing beta decay.

III-16: Old Gold Formation of Elements Radioactive decay happens in the natural world around us. Fission can be spontaneous for unstable nuclei, or it can be provoked using nuclear bombardment and other methods. Fusion of nuclei to form different isotopes happens in the stars.