Chem exam 3

Whatis avagadro’s number?

6.022 × 10²³

What is the molecular formula equation?

n • emipirical formula

What is the n in the molecular formula equation?

Molar mass/ mass of EF (will be given sometimes called the empirical mass)

What is the molar mass?

The mass IN GRAMS of one mole of an element or compound

What is the percent composition

The percentage, BY MASS, of each element in one mole of a COMPOUND

What is the equation for percent composition?

Mass of element in one mole of a comp. / Total molar mass of compound x 100

What factors can you not convert between?

Grams and particles

What do you use to convert grams into moles or moles into grams?

Molar mass

What do you use to convert moles into particles or particles into moles?

Avagadro’s number

What are empirical formulas?

Compound formulas that show the smallest, whole number ratios of atoms/moles of each element in a compound

What are metallic bonds

Occur between a metal and a metal, electrons delocalize creating CATIONS

What are covalent bonds?

Occur between a non metal and another non metal. Valence electrons are shared between atoms

What are ionic bonds

Occur (usually) between metal and a non metal. Electrons are transferred from one atom to another

What are ionic compounds?

Made from ionic bonds, the cation (usually metal) is written first, followed by the anion (usually non metal)

What does net neutral mean?

Found in ionic compounds, charges of ions that make up a compound must completely cancel

What is the charge of an element in group 1?

+1

What is the charge of an element in group 2?

2+

What is the charge of an element in group 15?

3-

What is the charge of an element in group 16?

2-

What is the charge of an element in group 17?

1-

What does it mean when a transition or post transition metal have a Roman numeral?

It represents the charge of the ion

Anything bonded with oxygen will…

Have the same charge

What is a polyatomic ion?

Ions made of more than one atom/element

If more than one polyatomic ion is needed in a compound…

you need to write the ion formula in parenthesis with subscript outside.

What are molecular compounds?

Made from covalent bonds, the names and formulas are based on the amount of each element in the compound.

What is an example of a polyatomic ion?

Ca (NO³)2

Example of a molecular compound formula

Diphosphorous Pentoxide

What are acids?

Compounds that start with hydrogen, hydrogen is bonded to an anion, and the anion charge determines the amount of hydrogen in a compound (neg charge is canceled by H)

What is the acid name if an anion ends in -ide?

(binary acid) Hydro____ic acid

What is the acid name if an anion ends in -ite?

____ous acid

What is the acid name if an anion ends in -ate?

____ic acid

What is the formula of Bromate?

BrO3

What is the formula of Iodate?

IO4