Unit 7- Naming, formulas, and chemical reactions

Question 1

Rule of zero

Answer 1

In ionic compounds, the positive charge of the metal and the negative charge of the nonmetal cancel each other out

Question 2

Molecular Formula

Answer 2

Shows the specific number of atoms in a molecule

Question 3

Empirical formula

Answer 3

Shows the simplest (smallest) whole number ratio of atoms in a molecule

Question 4

Ionic bond

Answer 4

Forms between a metal and nonmetal

• there is complete electron transfer
• END is greater than 1.69

Question 5

Covalent bond

Answer 5

Formed between two nonmetals
- shared electrons
- END between 0-1.69
- nonpolar (0-0.3) vs polar (0.3-1.69) covalent
— describes the strength of pull from each atom

Question 6

Coefficient

Answer 6

Shows number of molecules

Question 7

Subscript

Answer 7

shows number of atoms

Question 8

Binary compound

Answer 8

Made from TWO elements

Question 9

Polyatomic ions

Answer 9

Group of charged atoms

Question 10

Ternary compound

Answer 10

Made from THREE elements

Question 11

Crisscross method

Answer 11

Look up the charges of the atoms
Cross over to find subscripts
Put in empirical formula
Check rule of zero

Question 12

Naming Ionic Compounds

Answer 12

Write the name of METAL first
Write the name of NONMETAL and add “ide”
*if metal has more than one charge, write the specific charge using Roman numerals

Question 13

Naming Covalent Compoynds

Answer 13

Write the name of the FIRST element
** if first element has subscript of 2 or more, add appropriate prefix
Write the name of the SECOND element and add “ide”
** add prefix (including if there is only one element)

Question 14

Covalent compound subscripts with prefixes

Answer 14

Mono = 1
Di = 2
Tri = 3
Tetra = 4
Penta = 5
Hexa = 6
Hepta = 7 
Octa = 8 
Nona = 9 
Deca = 10

Question 15

Charge of Transition Metals in Compound

Answer 15

Determine charge of NONMETAL first

Then choose charge for transition metal that satisfies rule of zero (charges cancel out)

Question 16

Physical Reaction

Answer 16

The way atoms are arranged doesn’t change *changes are only intermolecular (between molecules- not atoms)
— reactants are not converted into different products

Question 17

Chemical reaction

Answer 17

The way atoms are arranged changes (intramolecular)

— break ionic and covalent bonds

Question 18

Determinants of Chemical Reaction

Answer 18

Release of heat and light (exothermic)
Absorbing heat (endothermic)
Production of gas (bubbles)
Formation of precipitate (solid) 
Change of color **not indicators**

Question 19

Parts of chemical reaction

Answer 19

Products= substances you end up with 
Reactants= substances you start with

Question 20

Law of Conservation of Mass

Answer 20

Mass can’t be created or destroyed in a chemical reaction

— the mass of the reactants= mass of products

Question 21

Symbols in Chemical Reactions

Answer 21

Arrow: separates reactants from products
+ = “and”
(S)= solid
(G)= gas
(L)= liquid
(Aq)= dissolved solid in solution
Double arrow: reversible reaction
Any symbol above arrow: needed for reaction
Element above arrow: catalyst needed for reaction

Question 22

Catalyst

Answer 22

Substance (enzyme) that speeds up the rate of reaction

Question 23

Ways to describe a chemical reaction

Answer 23

Sentence: copper reacts with chlorine to form copper (II) chloride

Word equation: copper + chlorine —> copper (II) chloride

Formula equation: Cu + Cl(2) —> CuCl(2)

Question 24

Name for NH(3)

Answer 24

Ammonia

Question 25

Diatomic elements

Answer 25

Atoms that do not occur alone in nature
Hydrogen, oxygen, Fluorine, Bromine, Iodine, Nitrogen, Chlorine (HOFBRINCL)
* all gases

Question 26

Name for CH(4)

Answer 26

Methane

Question 27

Colors of gases

Answer 27

Cl(2)= green 
H(2)= colorless
I(2)= purple 
CO(2)= colorless 
NO(3)= orange/brown

Question 28

Balancing Equations Rules

Answer 28

1) balance by adding coefficients
* save oxygen and hydrogen for last

2) reduce to lowest whole number

Question 29

“Never” for balancing equations

Answer 29

1) change subscripts

2) add coefficients in the middle of compounds

Question 30

Synthesis reaction

Answer 30

2 substances (elements or compounds) combine to produce one complex compound

Question 31

Decomposition reaction

Answer 31

One compound splits apart into two or more substances (simpler)

Question 32

Synthesis Reactions

Answer 32

Two substances joining together

• two reactants, one product
• create a complex compound

Question 33

Decomposition Reaction

Answer 33

One compound splits into two (or more) substances

• 1 reactant, two products
• diatomic elements*

Question 34

Single replacement reaction

Answer 34

One element replaces another if it is more ACTIVE

• one of the reactants is always an element and the other is a compound
• don’t carry subscripts over *
• water as HOH*

Question 35

Double Replacement reaction

Answer 35

Metals of two different compounds switch places

• products: one soluble and one non soluble
• metals replace metals
• Nonmetals replace nonmetals

Question 36

Combustion reaction

Answer 36

The reaction of oxygen gas with a compound

• synonym: burning
• products are always CO2 and H2O (complete combustion)
• Carbon first, then hydrogen, then oxygen

Question 37

What is the reaction

2H(2) + O (2) —> 2H(2)O

Answer 37

Synthesis

Question 38

What is the reaction

Zn + H(2)SO(4) —> ZnSO(4) + H(2)

Answer 38

Single replacement

Question 39

What is the reaction

Ca(OH)(2)+ H(2)SO(4) —> CaSO(4) + 2H(2)O

Answer 39

Double replacement

Question 40

What is the reaction

2H(2)O —> 2H(2) + O(2)

Answer 40

Decomposition

Question 41

Activity vs Reactivity

Answer 41

Activity= an ordered series showing which elements will replace each other in a chemical reaction
- most active in group 1: Lithium

Reactivity=how easily a chemical reaction will take place
- most reactive in group 1: Francium