Chapter 2: Atoms, Ions, and Molecules

Question 1

Milikan

Answer 1

credited with first measuring charge of electron

Question 2

JJ Thompson

Answer 2

proposed a plum pudding model in which the atom was a diffuse sphere of positive charge with negatively charged electrons embedded in the sphere(like raisins in an English plum pudding muffin)

Question 3

Rutherford

Answer 3

• discovered alpha particles were deflected by an electric or magnetic field in the opposite direction of beta particles; aplha particles were considered positive while beta particles were considered negative(in general)
• would disprove of the plum pudding model with the Rutherford- Geiger - Marsden experiment

Question 4

Rutherford - Geiger - Marsden experiment

Answer 4

alpha particles from a radioactive source were allowed to strike a thin piece of gold foil; to prove Thompson’s model the alpha particles would have to pass through

• Although alpha particles passed through, some bounced off widely or bounced back the way it came; this disproved the plum pudding model because of the wide deflections that occurred
• would lead to the assumptions of atoms consisting of positively charged nucleus surrounding a cloud of negatively charged ions

Question 5

James Chadwick

Answer 5

Rutherford’s student, discovered and characterized neutrons

Question 6

Groups in the periodic table?

Answer 6

vertical columns

Question 7

periods in the periodic table?

Answer 7

horizontal rows

Question 8

Identify groups in the periodic table

Answer 8

Group 1 - Alkali metals(excluding hydrogen!)

Group 2 - Alkali earth metals

Ten groups between 2 and 13 - transitions elements/metals
(between groups 3 and 4 are lanthinides and actinides; inner transition elements)

Metalloids - Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium, and Astatine(MARKED WRONG ON PAPER)

Nonmetals - hydrogen, elements in groups 14-18(excluding known metalloids)

Halogens are group 17 while noble gases are group 18

Question 9

Compounds of Elements that form one Cation/Ion: +1

Answer 9

hyodrogen, lithium, sodium, potassium, and cesium (group 1/1A)

silver ( transition element Ag)

Question 10

Compounds of elements that form one Cation/Ion: +2

Answer 10

magnesium, calcium, strontium, barium (group 2/2A)

zinc, cadmium (transition elements)

Question 11

Which element forms only a +3 Cation/Ion?

Answer 11

Aluminum (transition element)

Question 12

Compounds of elements that form one Anion/Ion: -1

Answer 12

fluoride, chloride, bromide, iodide (group 7/17)

hydride

Question 13

Compounds of elements that form one Anion/Ion: -2

Answer 13

oxide and sulfide (group 6/16)

Question 14

Element that only forms a -3 Anion/Ion?

Answer 14

nitride (group 5A/15)

Question 15

Ionic Compounds: Binary Ionic Compounds

Answer 15

• between a metal and a nonmetal
• lists the cation ion first and the anion second
• cation and anion are monatomic
• cation name stays the same for the metal(often ends in “ium”)
• anion name adds suffix ide to the nonmetal

Question 16

How to determine Formulas of binary ionic compounds

Answer 16

the charge(without the sign) of one ion becomes the subscript of the other

the positive charges of the cations balance the negative charges of the anions; compound has zero net charge

Question 17

Ionic Compounds that form more than one Ion

Answer 17

Systematic Name: lists the cation first and anion second; roman numerals are used with the cation name; the anion adds the suffix ide to the root

Common Name: suffix “ous” for the ion with the lower charge; suffix “ic” for the ion with the higher charge

Question 18

Molecular Masses/Formula Mass

Answer 18

• sum of atomic masses found on the periodic table
• ex: in H2O, would find the sum of two hydrogen and one oxygen
• molecular mass refers to covalent compounds while formula mass refers to ionic compounds

Question 19

Covalent Compound Names

Answer 19

• first element in formula is first part of name
• change the second word to having an “ide” suffix
  -include prefixes(mono,di, tri, tetra, etc.) to modify/show the number of that element present
• mono prefix is not used when first element has only one of it present

Question 20

Oxoanions

Answer 20

• polyatomic anions containing oxygen in combination with one or more other elements
• most oxoanions have a named based on the name of the element that appears first in the formula, with its ending changed to either ite or ate
• Example: SO_4^2- = Sulfate