05 Chemical formulas as conversion factors

Chemical formulas as conversion factors

Represent the number and type of elements in a compound.

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Chemical formulas

Poll

How ready do you feel to use chemical formulas as conversion factors?

• Not ready at all

• Somewhat ready

• Super ready

• I'm the conversion factor master

For the following questions, we'll be using the compound Iron (III) sulfate

Dropdown

In iron (III) sulfate, iron is the ​

Select answer

and sulfate is the ​

Select answer

Multiple Choice

Which is the symbol of the sulfate ion?

• 
  $$\left(SO_4\right)^{-3}$$

• $$\left(SO_4\right)^{-2}$$

• $$\left(SO_3\right)^{-4}$$

• $$\left(SO_3\right)^{-3}$$

Multiple Choice

Based on the charge of the sulfate ion, which is the charge used by iron in iron (III) sulfate?

• 2

• 3

• 1

• 4

Draw

Which is the chemical formula for iron (III) sulfate?

Draw

Write the two possible conversion factors that relate the iron (III) sulfate compound with the number of oxygen atoms

Open Ended

If you have 2.78 moles of iron (III) sulfate, how many oxygen moles would be available?

Open Ended

If you actually need 40 moles of oxygen, how many moles of iron (III) sulfate would be requiered?

For the following questions, you have to think fast about the equalities in chemical formulas

Multiple Choice

Number of magnesium ions in MgS

• 1

• 2

• 3

• 4

Multiple Choice

Number of hydrogens in $$H_2O$$

• 2

• 1

• 3

• 4

Multiple Choice

Number of chlorine ions in $$Ca\left(ClO_3\right)_2$$

• 2

• 3

• 4

• 1

Multiple Choice

Number of oxygen atoms in $$Al_2\left(SO_3\right)_3$$

• 3

• 12

• 1

• 9

Good! Now lets construct conversion factor faster

Draw

A conversion factor for sodium ions in NaCl

Draw

A conversion factor for aluminum ions in Al₂S₃

Draw

A conversion factor for phosphorous in Ca₃(PO₄)₂

Finally, lets use the conversion factor for solving problems

Multiple Choice

How many moles of calcium are in 4.5 moles of CaO

• 4.5 mol Ca

• 9 mol Ca

• 2.25 mol Ca

• 1 mol Ca

Open Ended

Number of oxygen moles in 4 moles of Li₂O

Open Ended

Number of chlorine moles in 5 moles of CaCl₂

Multiple Choice

Calculate the moles of oxygen in 6.5 moles of Al₂O₃

• 19.5 mol O

• 2.16 mol O

• 13 mol O

• 3.25 mol O

Open Ended

Number of CaS moles that contain 6 moles of S

Open Ended

Number of Al₂O₃ moles that contain 12 moles of oxygen

Multiple Choice

How many moles of Ca₃N₂ are needed to obtain 24 moles of N

• 12 mol Ca₃N₂

• 48 mol Ca₃N₂

• 8 mol Ca₃N₂

• 72 mol Ca₃N₂

Poll

How ready do you feel to use chemical formulas as conversion factors?

• Not ready at all

• Somewhat ready

• Super ready

• I'm the conversion factor master