Principles of Chemistry D-E

for section e (Chemical formulae, equations and calculations), it is more useful to do practice questions using the calculations than flashcards.

How are the elements arranged in the periodic table?

in order of atomic number and in groups and periods

How many electrons can shells hold?

2,8,8

Groups

Columns

Periods

rows

Metal Propeties

Good conductor of electricity and basic oxide

Non metal properties

Poor conductor of electricity and acidic oxides (some are neutral)

Base

a chemical substance with a pH higher than 7 (alkaline)

Where are the metals in the periodic table?

On the left

Where are the non-metals in the periodic table?

on the right

Elements in the same group have..

the same number of outer electrons

Group 1 metals are reactive

as you go down the group

Group 7 elements are reactive

as you go up the group

The group number on the periodic table indictates

the number of electrons in the outer shell

Why are noble gases unreactive?

Because they have a full outer shell

How to calculate Mr

add up the atomic masses of all the atoms

Mol

the unit for the amount of a substance

Percentage yield calculations

Molecular formula

the formula that shows the number and type of each atom in a molecule

Empirical formula

the simplest whole number ratio of each atom