Chapter 3 - Relative Formula Mass

Question 1

What is the Relative formula mass?

Answer 1

The relative formula mass is the amount of atomic mass it has each substance.

An example is: SiO2

32+(16*2)= 64

Question 2

Moles???

Answer 2

Is the chemical amount measured in moles. The symbol fo this is mol.

1 mol of this substance is te relative formula mass in grams

Eg~ Silicon = 32g

Question 3

Triangle for moles

Answer 3

Mass of grams (m) = Number of moles (n) * Molar mass (M or Mr)

Question 4

Triangle for Moles in concentration?

Answer 4

Concentration of solution (c) = number of moles (n) ÷ volume (v)

Concentration of solution is measured in = mol dm-3

Volume is measured in = dm3

Question 5

How to convert from dm3 to cm3 and opposite?

Answer 5

From dm3 to cm3 = * 1000

From cm3 to dm3 = ÷ 1000

Question 6

What is percentage yield?

Answer 6

Theoretical yield:

If you take 10 penalties, what is the maximum you can score = 10

Theoretical theory

If you only score 8, what is your percentage= 80%

Percentage yield

Question 7

What is the atomic economy?

Answer 7

The atomic economy is the mass of product you want want as a % of the mass of all the products you make.

An example:

CuO + H2SO4 —> CuSO4 + H2O
V V V V
79.5 98 159.5 + 18

Question 8

Triangle for calculating gas volume

Answer 8

Volume (v) = Number of moles (n) ÷ 24

Or.

Volume (v) = number of moles (n) * 24

Question 9

What are titrations?

Answer 9

Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the concentration of an identified analyte. Since volume measurements play a key role in titration, it is also known as volumetric analysis.