Chemical Formulas and Names

Question 1

what are the two types of compounds?

Answer 1

• ionic compounds

- covalent compounds

Question 2

what is in ionic bonding?

Answer 2

-electrons are transferred from metal to non metal atoms

Question 3

how is an ionic bond formed?

Answer 3

• by the attraction between positive and negative ions

- made up of metal and non metal

Question 4

steps to write ionic compounds?

Answer 4

1. write metal ion
2. write non metal ion
3. change non metal ending to ide

Question 5

why must the positive charges balance the negative charges in an ionic compound?

Answer 5

-the overall charge is zero

Question 6

what are metals with more than one ion charge?

Answer 6

-multivalent metals

Question 7

how to know which ion of a multivalent metal to use for a specific compound?

Answer 7

-roman numerals in the name

Question 8

what do roman numerals show?

Answer 8

-the charge of the metal ion

Question 9

when is a roman numeral needed?

Answer 9

-when an element has more than one possible ion charge

Question 10

when is a roman numeral not needed?

Answer 10

-when an atom only has one possible ion charge

Question 11

what are polyatomic ions?

Answer 11

• several atoms joined tgt with covalent bonds

- the whole group has a charge not the individual atoms

Question 12

when to use brackets around polyatomic ions?

Answer 12

-when there is more than one in the formula

Question 13

how to know if you are dealing with a polyatomic ion?

Answer 13

-there are more than two elements or the formula contains three or more capital letters

Question 14

if a polyatomic ion has a positive charge what does it act as?

Answer 14

-metal

Question 15

if a polyatomic ion has a negative charge what does it act as?

Answer 15

-non metal

Question 16

what do the molecules in covalent compounds do?

Answer 16

-share electrons

Question 17

covalent bonds occur between?

Answer 17

-two or more non metals

Question 18

what do prefixes indicate?

Answer 18

• number of atoms in the molecule

- written before atom name

Question 19

naming covalent compound steps?

Answer 19

1. use prefixes to show amount of each atom

2. change ending of second atom to ide

Question 20

what happens if there is only one atom of the first element?

Answer 20

-no prefix is used

Question 21

-what does the chemical formula of a covalent compound tell us?

Answer 21

-number of atoms of each element in the compound

Question 22

what do ionic compound subscripts show?

Answer 22

-smallest whole number ratio between the ions in the compound

Question 23

what do covalent compound subscripts show?

Answer 23

-the actual number of atoms in the molecule

Question 24

what do lewis diagrams show?

Answer 24

-arrangment of valence electrons around the nucleus of an atom

Question 25

what are not shown in lewis diagrams?

Answer 25

-inner electron shells with electrons

Question 26

what happens after bonding in LD?

Answer 26

-no more electrons are shown in the ion

Question 27

LD shortcut for metals?

Answer 27

-always have no electrons

Question 28

LD shortcut for non metals?

Answer 28

-always have full shell of electrons

Question 29

if there is more than one non metal how should it be drawn?

Answer 29

-separated

Question 30

what is there not in covalent compounds?

Answer 30

-no transfer of electrons or ions

Question 31

what are bonding pairs?

Answer 31

-electron pair being shared between the two non metals

Question 32

what are lone pairs?

Answer 32

-pairs of electrons that aren’t shared (2)

Question 33

how many diatomic elements are there?

Answer 33

• 7

- hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, iodine

Question 34

what do diatomic elements never occur in?

Answer 34

-single atom

Question 35

when are they most stable?

Answer 35

• when bonded with another atom of the same element

- they create double bonds

Question 36

what do diatomic elements consist of and why can they be called diatomic molecules?

Answer 36

• consists of two atoms

- have a covalent bond

Question 37

what is a chemical change?

Answer 37

• changes that produce new kinds of matter with different properties
• new substance created
• process known as chemical reaction
• is not easily reversed

Question 38

what is a physical change?

Answer 38

• change that does not produce new substances
• temperature, size, physical state can be altered
• can be easily reversed

Question 39

examples of chemical changes?

Answer 39

• digesting food
• burning match
• milk sours
• cooking of food
• chemical reaction

Question 40

examples of physical changes?

Answer 40

• boiling liquid
• cutting paper
• freezing water
• silver melting
• paper towel absorbs water