C4:Chemical calculations

Question 1

What atom is relative atomic mass compared to?

Answer 1

Carbon

Question 2

what is Ar (little r)

Answer 2

relative atomic mass

Question 3

How to find Mr

Answer 3

add all relative atomic masses in the formula (times by little numbers)

Question 4

triangle for solid

Answer 4

mass
moles x Mr

Question 5

triangle for liquid

Answer 5

moles
conc x vol

Question 6

triangle for gas

Answer 6

vol
mol x 24

Question 7

percentage yield

Answer 7

(actual mass of product/maximum theoretical mass of product)X100

Question 8

What are the factors affecting percentage yield.

Answer 8

-reaction may be reversible and re-form reactants again
-unwanted products
-human error (left in apparatus)
-lost during separating
-may not be pure.

Question 9

What is atom economy?

Answer 9

a measure of the extent to which the atoms in the reactants end up in the desired products.

Question 10

Where do products not in the atom economy go?

Answer 10

Landfill (environmental issues)

Question 11

how to calculate atom economy: (%)

Answer 11

(%)=(Mr of desired product/sum of Mrs of reactants)X100