Mole/Grams Conversion• Find mass ratios• Review the calculation of gram formula mass.• Define moles in terms of mass and grams in terms of

moles. • Calculate the number of grams when the number of

moles of a substance is given & calculate the number of moles when the mass of a substance is given.

Aim: How do We Convert Grams to Moles and Moles to Grams?

Essential Questions:

1. How can we define moles in terms of mass and mass in terms of moles?

2. How do we find the mass ratio of elements?

3. How do we Calculate the number of grams when the number of moles of a substance is given & how do we calculate the number of moles when the mass of a substance is given? Use examples to illustrate your answer.

Key Words:Moles, grams, atomic ratio, gram ratio,Avogadro’s

Do Now

1. The empirical formula of a compound is NO2; its molecular mass is 92g/mol. What is its Molecular formula?

Do Now1. Refer to the following compound to answer the

questions below:

C2H6

A. What is the ratio of carbon atoms to hydrogen atoms?

B. What is the mass ratio of carbon to hydrogen?

C. What is the gram formula mass?

What is One Mole of a Substance?

Examine the Display!

Mole & Grams

1 mol of a substance = 1 gram formula mass (GMF) of that substance.

1 gram formula mass (GFM) of a substance = 1 mole of that substance.

Find the Mass of the Common Substances Below

What is the weight of 1 mole of:

1. Water

2. Oxygen

3. Hydrogen

4. Table Salt

Converting Moles Grams

How many grams are in 10 g of water?

How about if I have 5 g?

What mathematical operation did you do to get to your answer?

Exercise

How many grams are in 3 moles of CH2?

Converting Grams Moles

How many moles are in 18 g of water?

How many moles are in 9 g of water?

What mathematical operation did you do to get to your answer?

Exercise

How many moles are in 270 g of glucose?