Periodic Table
What type of elements (metals, nonmetals, or metalloids) are most common on the Periodic Table?
Metals
What two particles make up most of the mass of an atom?
protons + neutrons
a. Na produces H2 when exposed to H2O
b. Cu turns green when exposed to air
a. chemical
b. chemical
Name another element with similar properties as each of the following elements:
a. Ca
b. F
c. Al
a. Mg, Ba(alkaline earth metal)
b. I, Cl, Br (halogen)
c. Ga, In (Group 3 metals)
Name the most common isotope of sodium.
Na-23
Name the element each of the following is referring to:
a. Alkali metal with 36 electrons as an ion
b. Halogen that is a liquid at room temperature
A. Rubidium
B. Bromine
How do you calculate the number of neutrons in the nucleus of an atom?
Mass number - atomic number
Physical or Chemical Changes?
a. sugar dissolves in water
b. iron conducts electricity
c. water turns into vapor
a. physical
b. physical
c. physical
Sodium's atomic radius is 100 ppm.
Rubidium's atomic radius is 225 ppm.
Estimate potassium's atomic radius.
~ 163 ppm
Which of the following tests will indicate you have a metal and not a nonmetal or metalloid if it is positive?
a. Appearance
b. Brittle/Malleable
c. Electrical conductivity
d. Reaction w/HCl
d. Reaction w/HCl
Give the name and symbols for 6 metalloids.
B-boron
Si-Silicon
Ge-Germanium
As-Arsenic
Sb-Antimony
Te-Tellurium
Po-Polonium
b. What types of elements form anions?
c. Give an example of an anion and a cation?
a. metals Ex: Na+1
b. nonmetals Ex: Cl-1
Give a specific example of a physical change for each of the following observations:
a. change in color
b. production of a gas
a. hydrates when heated change color, painting a wall, adding food coloring to water
b. water evaporating, carbon dioxide leaving pop, dry ice sublimating
Name two trends in the halogens as you go from top to bottom down the group.
1. size of atoms increases
2. atomic mass increases
3. reactivity decreases
4. electronegativity decreases
5. ionization energy decreases
6. electron affinity decreases
Metal or Nonmetal?
Forms anions, brittle, gas at room temperature
Nonmetal
Why is the atomic mass listed on the periodic table a decimal if an element's mass is the number of protons and neutrons in the nucleus?
It represents the weighted average of all the isotopes of that element.
Calculate the number of protons, neutrons, and electrons in I-129.
Protons = 53
Neutrons = 127-53 = 76
Electrons = 53
Give an examples of a specific chemical change for each of the following observations:
a. production of a gas
b. color change
a. metals reacting with acids to produce hydrogen, baking soda and vinegar makes carbon dioxide, burning wood gives off carbon dioxide
b. iron rusting, apple turns brown when exposed to air, copper turns green when it is exposed to air
Why are period trends (horizontal left to right) more unpredictable than group trends (vertical up and down)?
Across a period there are different types of elements (metals, metalloids, nonmetals). Down most groups you have only 1 type of element.
Describe two tests you could perform to discriminate between a metal and nonmetal. Give the results of each test that would indicate a metal.
1. Electrical conductivity - metals are conductive
2. Crushing - metals are malleable
3. Rxn with acid - metals react and produce H2 gas
a. Name 3 monatomic gases at room temperature
b. Name 3 diatomic gases at room temperature
c. Name 1 diatomic liquid at room temperature
a. He, Ne, Xe, Rn
b. O2, N2, H2, Cl2
c. Br2
Write the correct isotopic symbol for the following particles:
a. atomic # = 15 neutrons = 17
b. atomic # = 20 neutrons = 18
a. 3215P
b. 4020Ca+2
Physical or Chemical Changes?
a. photosynthesis
b. eat a hamburger
c. light bulb burns out
d. snow sublimes
e. salt dissolve
a. chemical
b. chemical
c. physical
d. physical
e. physical
State the trend down a main group for each of the following properties:
a. electronegativity
b. atomic radius
c. mass
d. metal reactivity
e. nonmetal reactivity
a. decreases
b. increases
c. increases
d. increases
e. decreases
Describe two specific properties for each of the following groups:
a. alkali metals
b. halogens
c. noble gases
a. +1 ions, most reactive metals, react with water to form basic solutions, 1 valence electron
b. -1 ions, most reactive nonmetals, 7 valence electrons
c. unreactive, gases, colorless, odorless, 8 valence electrons