P1C14 - Quantitative analysis

Question 1

How do you calculate the concentration of a solution? (In terms of mass)

Answer 1

Solution concentration (g/dm3) =

Mass of substance (g)
——————————-
Volume (dm3).

Question 2

How do you calculate the concentration of a solution? (In terms of moles)

Answer 2

Solution concentration (mol/dm3) =

Amount of substance (mol)
/
Volume (dm3).

Question 3

What IS the value for room temperature?

Answer 3

20C

Question 4

What percentage is the percentage yield always under?

Answer 4

100%

Question 5

What are side reactions?

Answer 5

Unexpected reactions where the intended product is not made.

Question 6

What 4 factors make sure percentage yield stays under 100%?

Answer 6

Side reactions
Separation difficulties
Chemicals stick to apparatus
Incomplete reactions

Question 7

How do you calculate percentage yield?

Answer 7

% yield =
(real yield ÷ theoretical yield)
× 100

Question 8

What is the theoretical yield?

Answer 8

The theoretical yield is the maximum mass of a product that could possibly be created from a reaction.

Question 9

What is the actual yield?

Answer 9

The actual yield is the mass of a desired product obtained from a reaction.

Question 10

How do you calculate Atom economy?

Answer 10

atom economy(%)=

    Mr of all desired products --------------------------------------------------
    Mr of reactants ​
                 ×100

Question 11

Which term is used to describe the amount of the reactants that end up as useful products?

Answer 11

Atom economy

Question 12

Why are Reaction pathways (ways reactions happen) with high atom economies good?

Answer 12

Save money
Low waste

Question 13

When looking at a reaction pathway, what do you consider?

Answer 13

• How much the reactants cost.
• What the percentage yield will be.
• How quickly the reaction will happen.
• How useful the by-products of the reaction are.
• The position of equilibrium.