2.1

Question 1

Define a mole

Answer 1

The amount of any substance containing as many particles as there are carbon atoms in exactly 12 g of the carbon 12 isotope

Question 2

Define avocadros constant

Answer 2

The number of atoms per mole of the carbon 12 isotope

Question 3

Define molar mass

Answer 3

mass per mole of a substance. The units are g mol ^ -1

Question 4

Define amount of a substance

Answer 4

The quantity that has moles as its unit… a way of counting atoms

Question 5

Relative isotopic mass

Answer 5

The mass of an atom of an isotope compared with one twelfth of an atom of carbon 12

Question 6

Relative atomic mass

Answer 6

Weighted mean mass of an atom of an element compared with one twelfth of the mass of an atom of carbon 12

Question 7

Define molar gas volume-

Answer 7

the volume per mole of a gas. The units of volume are dm3 mol -1. At room temp and preassure the molar volume is approximately 24.0 dm 3 -1

Question 8

define molecular formula

Answer 8

the number of atoms of each element in a molecule

Question 9

define empirical formula

Answer 9

the simplest whole number ratio of atoms of each element in a compound

Question 10

define percentage yield

Answer 10

maximum amount of product you can obtain.

Question 11

examples of bases

Answer 11

metal oxides, metal carbonates

Question 12

define oxidation numbers

Answer 12

the number of electrons LOST OR GAINED OR SHARED by an atom in a compound

Question 13

what oxidation numbers do unconbined elements have

Answer 13

0xidation number 0=== no charge

Question 14

define what is meant by polyatomic ions

Answer 14

similar compounds but the sum of the oxidation numbers adds up to the charge on the ion

Question 15

difference between an oxidising agent and a reducing agent

Answer 15

an oxidising agent oxidises something else and reduces itself

a reducing agent, reduces something else and oxidises itself

Question 16

what happens to the oxidation number when oxidation increases

Answer 16

oxidising number increases eg 2- to 3+ charge

Question 17

what are oxyanions

Answer 17

negative ions with oxygen

Question 18

what do the names of oxyanions end in

Answer 18

-ate

Question 19

name some ions ending in ide

Answer 19

Sulfide (S 2-)
nitride (N 3-)
oxide (O 2-)

Question 20

who discovered the proton

Answer 20

Rutherford

Question 21

who discovered the neutron

Answer 21

James Chadwick

Question 22

Outline Daltons atomic theory

Answer 22

atoms are tiny particles that make up elements.
different elements are made up of different atoms
atoms cannot be divided

Question 23

Outline JJ Thompsons plum pudding atom theory

Answer 23

JJ discovered that cathode rays have negative charges
could be deflected by both magnet and electric fields
very small mass

Daltons idea that atoms could not be split any further was disapproved.

JJ proposed that negative electrons move around in a sea of positive charge.
atom has no overall charge

Question 24

Outline Rutherford’s gold leaf experiment and its findings

Answer 24

Directed alpha particles towards a sheet of thin gold foil.
the plum pudding model should’ve had no deflections but his findings were;

Most particles deflected as expected
some deflected at large angles
very few particles actually deflected back to the the source

he then proposed:
electrons orbit the nucleus
positive charge and most of the atoms mass is concentrated in the nucleus.