Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and...

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Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH4NO3) 3. Ca(C2H3O2)2 4. If I had 124 g of Ca(C2H3O2)2, how many grams of Hydrogen would I have?

Transcript of Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and...

Page 1: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Homework Check• Find the percent composition of the following:

1. A compound with 222.6 g of Na and 77.4 g of O

2. Ammonium Nitrate (NH4NO3)

3. Ca(C2H3O2)2

4. If I had 124 g of Ca(C2H3O2)2, how many grams of Hydrogen would I have?

Page 2: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Empirical Formula

Percent to Formula

Page 3: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

• Molecular formula: Shows the number and kinds of atoms actually present

• Empirical formula: Gives the simplest ratio between atoms

H2O2

HO

moles

Page 4: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

4 Steps to Find the Empirical Formula

1.Replace the percent with grams

2.Convert grams to moles using the fence diagram

3.Divide the moles by the smallest number of the moles

4.If the ratio is not a whole number, then multiply to get a whole number mole ratio. (If the ratio is close to a whole number—0.1 away—then just round it off.)

Page 5: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Rhymes to Remember

Percent to Gram

Gram to Mole

Divide by Small

Multiply till Whole

Page 6: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Practice!

1.N = 36.8% O = 63.2%

2.C = 44.45% H = 6.21% O = 49.35%

Page 7: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Telephone Game

C = 46.15% H = 7.74% O = 46.11%

Page 8: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Warm-Up! (Day 4)• Find the empirical formula of a compound that

contains 40.9% carbon, 4.50% hydrogen, and 54.6% oxygen.

Page 9: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

• Molecular formula: Shows the number and kinds of atoms actually present

• Empirical formula: Gives the simplest ratio between atoms

H2O2

HO

moles

Page 10: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Steps to find the Molecular Formula

1. Calculate the molar mass of the empirical formula

2. Divide the actual molar mass by the empirical formula’s mass

3. Multiply the empirical formula’s subscripts by the answer from step #2

Page 11: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Practice!• A compound has a molar mass of 58.2 g/mol. If its

empirical formula is C2H5, what is the molecular formula?

Page 12: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Try these! (on a separate piece of paper)

1. What is the molecular formula that has a molar mass of 176 g/mol and its empirical formula is C3H4O3?

2. What is the molecular formula that has a molar mass of 194520 g/mol and its empirical formula is C6H10O5?

Page 13: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Warm-Up! (Day 5)• Write the Rhymes for the empirical formula.

Page 14: Homework Check Find the percent composition of the following: 1. A compound with 222.6 g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.

Rhymes to Remember

Percent to Gram

Gram to Mole

Divide by Small

Multiply till Whole