Unit 3 – review for finals These are the topics you should know and be able to answer questions about: 1. The periodic table a. Where are the metals are located. i. Left of stair step b. Where the non-metals are located. i. Right of stair step c. Where the metalloids are. i. They are the stair step d. Where the transition metals are located. i. Groups 3 - 12 e. What are the characteristics of metals, nonmetals, and metalloids? i. Metals I. Luster (shininess) II. Good conductors of heat and electricity III. High density (heavy for their size) IV. High melting point V. Ductile (most metals can be drawn out into thin wires) VI. Malleable (most metals can be hammered into thin sheets) ii. Nonmetals I. No luster (dull appearance) II. Poor conductor of heat and III. electricity IV. Brittle (breaks easily) V. Not ductile VI. Not malleable VII. Low density VIII. Low melting point iii. Metalloids I. Solids II. Can be shiny or dull III. Ductile IV. Malleable V. Conduct heat and electricity better than nonmetals but not as well as metals f. Which types of elements conduct electricity? i. Metals and metalloids 2. Metals vs. nonmetals a. What is the difference between a metal and a nonmetal in regards to their properties? i. List the properties of metals. ii. List the properties of nonmetals. iii. Metals I. Luster (shininess) II. Good conductors of heat and electricity III. High density (heavy for their size) IV. High melting point V. Ductile (most metals can be drawn out into thin wires) VI. Malleable (most metals can be hammered into thin sheets)

iv. Nonmetals I. No luster (dull appearance) II. Poor conductor of heat and III. electricity IV. Brittle (breaks easily) V. Not ductile VI. Not malleable VII. Low density VIII. Low melting point v. 3. Subatomic particles a. How do you calculate the various subatomic particles? i. What number gives you the number of protons? I. Atomic number ii. How do you determine the neutrons? I. Use atomic mass – number of protons iii. How do you determine the electrons? I. Electrons are equal to the protons if there is no charge II. If there is a positive charge, you have lost electrons so subtract the charge III. If there is a negative charge, you have gained electrons so add the charge REMEMBER THAT THE NUMBER OF PROTONS IS ALWAYS EQUAL TO THE ATOMIC NUMBER. THIS NUMBER NEVER CHANGES!! Isotope

Nuclear Symbol

Protons

Neutrons

Electrons

3

4

3

6c

6

14 – 6 = 8

6

26Fe

26

30

26

10

21 – 10 = 11

10

13

15

13

79Au

79

128 – 79 = 49

79

26Fe

26

30

26

Lithium – 7

7

Carbon - 14

14

3Li

Iron - 56

56

Neon - 21

21

Aluminum – 28

28

Gold - 128

128

Iron - 56

56

10Ne

13Al

4. Ion a. What is an ion? i. An ion is an element with a charge, positive (+) or negative (–) ii. Ions are formed when the number of electrons are changed iii. Have same number of protons, but different number of electrons iv. This means that they have a charge ( a positive or negative sign and number after the element symbol) b. What are the charges of the 8 major groups on the periodic table? i. Group 1 = +1 ii. Group 2 = +2 iii. Group 13 = +3 iv. Group 14 = +4 or -4 v. Group 15 = -3 vi. Group 16 = -2 vii. Group 17 = -1 viii. Group 18 = 0 c. What does it mean to have a positive charge? Negative charge? I. If there is a positive charge, you have lost electrons so subtract the charge II. If there is a negative charge, you have gained electrons so add the charge d. What is a cation? Are these metals or nonmetals? i. Positively charged ion ii. Metals e. What is an anion? Are these metals or nonmetals? i. Negatively charged ion ii. Nonmetal f. How do the number of electrons and protons compare to each other with an ion? i. Cation = positive I. There are more protons than electrons present ii. Anion = negative I. There are more electrons than protons present g. Which one below is an ion? i.

ii. +

4p 5 n0

iii. +

4p 6 n0

4 p+ 6 n0

The ion would be the one with a different number of protons and electrons. The only one that matches this is option iii.

h. A model of the sodium atom is shown below. What is the electric charge of this ion?

11 p 12 n

If you count up the number of electrons present, you will see that there are only 10 electrons but there are 11 protons. This means that this ion has a charge of +1 because it has lost an electron. This also means that it has one more proton than electron. 5. Isotopes a. What is an isotope? i. Atoms that have the same number of protons, but the number of neutrons have changed ii. These are what are commonly used in nuclear chemistry iii. You can tell you have an isotope because the mass number you are using is different than what is listed on the periodic table or because the neutrons are different than what it should be from the periodic table b. What changes with an isotope? i. The mass number is different than what is on the periodic table because the number of neutrons is different c. All atoms of a given isotope of the same element, have the same _____ but different ______. i. Atomic number ii. mass

37

Cl-

6. What are the subatomic particles in: a. How many protons: 17 b. How many neutrons: 37 – 17 = 20 c. How man y electrons: 17 + 1 due to charge = 18 7. Electron configuration a. What do the different electron cloud shapes look like (s, p, d, f)

S

P

D

F

b. Which of the orbitals shapes is spherical? i. s c. What is the electron configuration for an element – how do you determine it? i. 1926: Schrödinger solved a mathematical problem describing the location and energy of an electron. ii. The Quantum Mechanical Model comes from that solution. I. Describes the probability of finding an electron in a certain position. (Think of this as “chance”) iii. The location of the electron is represented as a fuzzy cloud around the nucleus where the electron is found 90% of the time.

Element

Electron Configuration

Valance Electrons

1

Ne

1s22s22p6

8

2

Ca

1s22s22p63s23p64s2

2

2 – all transition metals only have 2 valence electrons (the 2 s shape cloud electrons that are before the d area)

3

Mn

1s22s22p63s23p64s23d5

4

Cl

1s22s22p63s23p5

7

5

C

1s22s22p2

4

8. Reactivity a. Where are the most reactive metals located? i. The most reactive metals are located near Fr on the periodic table ii. Fr is the most reactive nonmetal b. Where are the most reactive nonmetals located? i. The most reactive nonmetals are located near F on the periodic table ii. F is the most reactive non metal c. Why are the noble gases nonreactive? i. What is it about the noble gases that makes them nonreactive? I. The noble gases have 8 valence electrons II. This makes them stable and won’t allow them to react III. They do not need to gain valence electrons, so they are nonreactive