Unit 5 - The Mole

Question 0

Law of Conservation

Answer 0

In any chemical reaction, mass is neither lost nor gained

Question 1

Antoine-Laurent Lavoisier

Answer 1

Chemistry into quantitative Science

Law of Conservation of Mass

Question 2

Joseph Louis Proust

Answer 2

Showed copper (||) carbonate in parts by mass
Law of Definite Proportions

Question 3

Law of Definite Proportions

Answer 3

In any compound, the elements are always present in different proportions by mass

Question 4

John Dalton

Answer 4

Hypothesized difference between atoms was in weight
Found relative atomic weights and numbers of atoms entering into compound forms
Law of Multiple Proportions

Question 5

Law of Multiple Proportions

Answer 5

If two elements combine to form different compounds, then the mass ratios of the second element to a fixed mass of the first element are always small whole numbers

Question 6

Avagadro’s Law

Answer 6

Equal volumes of different gases, at the same temperature and pressure contain the same number of particles

Question 7

The Mole

Answer 7

The number of carbon-12 atoms in 12g of carbon-12
SI unit for amount
Equal to Avagadro’s number: 6.02 * 10^23

Question 8

Molar Mass

Answer 8

Atomic mass in grams

Question 9

Molar Volume of a Gas

Answer 9

Volume occupied by 1 mol of gas particles

Question 10

STP

Answer 10

Standard temperature and pressure
0 degrees Celsius and 101.3kPa
At STP molar volume of any gas is 22.4L

Question 11

Percentage Composition

Answer 11

The percentage of each element in the compound by mass

Question 12

Empirical Formula

Answer 12

The smallest integral (integer) ratio of the different atoms in a molecule

Question 13

Molecular Formula

Answer 13

The actual number of each type of atom

N=molar mass of molecular formula/molar mass of empirical formula

Question 14

Concentration of a solute in a solution

Answer 14

the amount of solute dissolved per unit of volume

Question 15

A concentrated solution

Answer 15

One with a relatively large amount of solute dissolved per unit of volume

Question 16

Dilute Solution

Answer 16

One with a relatively small amount of solute dissolved per unit of volume

Question 17

Molar Concentration (molarity) of a solute in a solution

Answer 17

The number of moles dissolved per litre of solution
C=n/V
n=cV

Question 18

Volumetric Flask

Answer 18

Bottom of miniscus will rest on the miniscus marker
Miniscus etch marker
Water miniscus sags
Mercury miniscus puffs

Question 19

Simple Dilution

Answer 19

Dilute a solution by simply adding more solvent
Since only adding solvent #moles before and after are the same
1=initial 2=final

C1V1=C2N2

C2=C1V1 * 1/V2

Question 20

Complex Dilution

Answer 20

Dilute/concentrate a solution by combining with another solution 
Moles will change
Total Volume= 
Total Moles= 
[x] =total mol/total litres