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Flashcards in Chemical calculations Deck (7)
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1
Q

What is Ar?

A

Atomic mass (mass of element)

2
Q

What is Mr?

A

Formula mass (combined mass of all elements in a compound)

3
Q

How do we calculate the percentage composition?

A
  1. Write formula of compound
  2. Calculate the Mr of compound
  3. Identify the element
    - Identify its Ar
    - Identify amount of atoms
4
Q

What is the equation to calculate the percentage composition?

A

%z = Ar(number of atoms of Z) (divided by) Mr of compound

5
Q

How do we find the percentage of oxygen in an atom?

A

Mass of oxygen (divided by) formula mass x 100

6
Q

How do we find the percentage mass?

A

%mass of an element = Relative atomic mass x number of atoms of the element (divided by) relative formula mass x 100

7
Q

How do you work out the empirical formula?

A

Mass (divided by) atomic mass