Periodic Law

Question 1

original periodic table was created by?

Answer 1

Dimitri Mendeleev

Question 2

An element’s period number(row) is the same as the number of energy levels that the electrons of its Atoms occupy. True or false

Answer 2

true

Question 3

all elements in each main group have the same number of valence electrons. True or false

Answer 3

true

Question 4

atomic radius increases as you go left and down. why?

Answer 4

valence electrons occupy energy levels further from the Nucleus
inner electrons shield the valence electrons from the attraction of the Nucleus

Question 5

1st ionization energy is

Answer 5

the energy required to remove an electron from an atom.

Question 6

elements react to end up with the same number of electrons as the nearest noble gas. what is this called

Answer 6

isoelectronic

Question 7

what is electron affinity

Answer 7

it is a measure of the change in energy that occurs when an electron is added to the outer energy level of an atom to form an negative ion.

decrease down a group
increase across a period

Question 8

VSEPR

applies only to ____

Answer 8

Covalent

Question 9

tetrahedral
# of bonding e pairs
# of lone e pairs
bond angles example

Answer 9

4
0
109.5
CH4

Question 10

trigonal pyramidal 
# of bonding e pairs
# of lone e pairs
bond angles
example

Answer 10

3
1
107.3
NH3

Question 11

bent (angular)
# of bonding e pairs
# of lone e pairs
bond angles
ex

Answer 11

2
2
104.5
H2O

Question 12

trigonal planar
# of bonding e pairs
# of lone e pairs
bond angles
ex

Answer 12

4
0
120
CH2O

Question 13

linear
# of bonding e pairs
# of lone e pairs
bond angles
ex

Answer 13

varies
varies
18p
CO2. H2. N2

Question 14

two or more elements and or small compounds react to form a larger compound
A +B -> C

Answer 14

synthesis

Question 15

compound breaks down into elements and or other compounds

C -> A + B

Answer 15

decomposition

Question 16

scientific name for burning.

reaction of an element or compound with oxygen to form the most common oxides of the elements that make up the compound

Answer 16

combustion

Question 17

what are the products of combustuon

Answer 17

carbon dioxide and water

Question 18

element in a compound is replaced by another element. what is this called. what are the two types

Answer 18

single displacement
metal replaces metal or hydrogen
non metal replaces non metal

Question 19

involves the exchange of positive ions (cations ) in aqueous solution (water)

AB + CD -> AD + CB

Answer 19

double displacement

Question 20

metals react with oxygen to form __

Answer 20

metal oxides. always SOLID

Question 21

metal oxides react in water to form ____

Answer 21

bases. basic oxidases

Question 22

non metals react with oxygen to form _____

Answer 22

non metal oxides. usually liquid or gas

Question 23

non metal oxides react in water to form ___

Answer 23

acids

or acidic oxides

Question 24

Heating hydrates causes it to decompose into an “____” ___ and ____

Answer 24

anhydrous salt and water vapour

Question 25

a carbonate when heated will decompose into ?

MgCO3

Answer 25

metal oxides and carbon dioxide gas

Question 26

decomposition of nitrates typically result in ?

ex. KNO3

Answer 26

nitrogen gas, oxygen gas, and a metal oxide

N2 + O2 + K2O

Question 27

decomposition of bicarbonate results in ?

NaHCO3

Answer 27

carbonate + water vapour + carbon dioxide

Na2CO3 + H2O + CO2