Percent Composition This tutorial will help you learn how to calculate the percentage by mass of elements in a compound.

Slides:



Advertisements
Similar presentations
Calculations What you need to know: Relative formula mass Empirical formula % composition by mass Use balanced equations to calculate masses of reactants.
Advertisements

GRAB A CALCULATOR AND GET OUT A PIECE OF PAPER FOR NOTES. Empirical Formulas.
Chem Catalyst 1) How many grams does 3.24 mol of carbon weigh? 2) How many particles are in 3.24 mol of carbon dioxide?
Additional Problem Sets
Empirical and Molecular Formulas. Formaldehyde CH 2 O Acetic acid C 2 H 4 O 2 Gylceradehyde C 3 H 6 O 3 40% C; 6.7% H; 53.3% O.
Intro to Quantities Review Problems These are the calculations you should be able to perform: Sum of molar mass for a compound Convert mass  mole Convert.
Percent Composition, Empirical and Molecular Formulas Courtesy
Calculating Percent Composition Mrs. Page 10 th Chemistry.
Percent Composition. What is Percent Composition?  The percent composition by mass of a compound represents the percent that each element in a compound.
CHAPTER 3b Stoichiometry.
Calculating Percentage Composition Suppose we wish to find the percent of carbon by mass in oxalic acid – H 2 C 2 O 4. 1.First we calculate the formula.
Chapter 10: Chemical Quantities
Jeopardy Molar Mass Avogadro’s Number Stoichiometry Limiting Reactant Emp/Molec Formula Q $100 Q $200 Q $300 Q $400 Q $500 Q $100 Q $200 Q $300 Q $400.
The Mole AA. Review Must turn in your packet with notes stapled to it before you can take the test.
Stoichiometry Balancing Equations Molecular and Empirical Formulas Percent Composition Mole Conversions
Chemical Formulas and Moles. Example: 1.water (C) – every molecule of water contains 2 atoms of hydrogen & one atom of oxygen - 2 molecules of H 2 O would.
STAAR Ladder to Success Rung 8. How do chemists define a mole? Example #1: A sample consists of 6.85 x atoms of carbon. How many moles does the.
7-3 Percent Composition & Formulas 1.Percent Composition/Percent by Mass (WS #1-4) 2.Empirical Formulas (WS #5-8) 3.Molecular Formulas (WS #9-13) 4.Lab.
27/05/2016 Relative mass formula, atomic mass, and empirical formula.
Quantitative Chemistry (Part 1) Isotopes Standard Atom for Mass Relative Atomic Mass Formula Mass Percentage Composition.
Percentages How do you calculate your percentage score in a test if you correctly answered 34 out of 47 questions? Answer: 33/47 x 100/1 = ? If 18 out.
 Mass of crucible + lid = g  Mass of crucible + lid + Mg = g  Mass of crucible + lid + magnesium oxide = g.
By: Hilary Megeney & Kristen Jorgensen Chemistry 11 adv.
Molar Mass Practice: Molar Mass Practice: 1. Find the molar mass of ammonium sulfate (also called the formula mass): 2. Find the molar mass of copper (II)
1 Chapter 10 “Chemical Quantities” Yes, you will need a calculator for this chapter!
THE MOLE Chapter 10: Chemical Quantities Measuring Matter What is a mole? It is the SI unit that measures the amount of substance.
Percent Composition. What is it? The percent composition by mass of a compound represents the percent that each element in a compound contributes to the.
Percent Composition, Empirical and Molecular Formulas Courtesy
Percent Composition. Percent composition refers to the percentage by mass, not percentage by the number of atoms in the compound. For example - H 2 O.
Percent Composition Percent by mass of an element in a compound.
In chemistry the unit we use to measure the “amount of a substance” is the mole The mole can be related to the # of particles (molecules or atoms), the.
a calculation used to determine the contribution of each element as a %age of the total mass of the compound There are 2 ways we can do this: 1) You are.
Empirical Formula Is the formula with the smallest whole-number mole ratio of the elements in a compound.
Catalyst – March 15, 2011 Give the formula AND name for the following covalent compound.
Percent Composition, Empirical and Molecular Formulas Courtesy
Unit 6: The Mole What is the MOLE? The Mole is a unit of measurement. ► Just as 1 dozen =12 ► x atoms = 1 mole ► Also called Avogadro’s Number.
Chemical Formulas. Mass Percent Also known as percent composition. Shows the mass of each element in a compound as a percent of the total mass of the.
Students type their answers here
Empirical Formulae The empirical formula of a compound is the simplest ratio of the different atoms in it. For example, for ethane (C2H6)it is CH3. You.
Percent Composition - The percent composition of a component in a compound is the percent of the total mass of the compound that is due to that component.
Percent Composition - The percent composition of a component in a compound is the percent of the total mass of the compound that is due to that component.
Percent Composition: Is the percentage of the total mass due to each element within a compound.
Percent Mass, Empirical and Molecular Formulas. Calculating Formula (Molar) Mass Calculate the formula mass of magnesium carbonate, MgCO g +
What do you notice about these formulae? C 2 H 4 C 3 H 6 C 4 H 8.
Percent Composition. Percent Composition by Mass – If you want to know what percentage of a compounds’ mass is contributed to by each element present.
Percent Composition.
Opener – do on a sheet of paper (or GOOS Paper
∆ KClO3 (s) KCl (s) + O2 (g) Purpose - Background -
Percent Composition Calculations
PERCENT COMPOSITION SCH3U.
Percent Composition, Empirical and Molecular Formulas
Stoichiometry Review.
Percent Composition, Empirical and Molecular Formulas
Chemical Formulas.
What is the mass of 1 mole of Uranium?
Percent Composition.
Percent Composition.
Relative Formula Mass This is the total mass of the sum of all the relative atomic masses of the elements in a compound.
Percent Composition.
Vocabulary Percent Composition -
Percent Composition.
Ch. 7: Chemical Formulas and Compounds
Law of definite and multiple proportions
Percentage Composition
Percent Composition.
Percent Composition Chapter 7-3, p
Ch. 7: Chemical Formulas and Compounds
III. Percent Composition
Presentation transcript:

Percent Composition This tutorial will help you learn how to calculate the percentage by mass of elements in a compound

What is the percentage of oxygen in Potassium chlorate? Place 1.29g of KClO 3 in a crucible and heat it for at least 10 minutes. Heating this compound will drive the oxygen atoms out of the compound and into the air as oxygen gas. After heating, allow the crucible to cool to room temperature.

The mass of the contents in the crucible is now 0.78g. All of the oxygen has been driven off and only KCl remains in the crucible. What is the mass of oxygen that was driven off?

CORRECT 1.29g – 0.78g = 0.51g of oxygen Now determine the percentage of oxygen in the compound by taking the mass of they oxygen divided by the mass of the compound and multiplying by 100. Show your work on your paper.

GOOD WORK (0.51g/1.29g)x 100 = 39.1% oxygen Let’s now do some problems when we only know the formula of the compound.

What is the mass of carbon in carbon dioxide? #1 – Find the mass of the atom. Carbon has a mass of 12.0g #2 – Find the mass of the compound CO 2 has a molecular mass of 44.0g. CO 2 has a molecular mass of 44.0g. #3 – Mass of atom/mass compound and then multiply by 100. (12.0/44.0) x 100 = 27.3% carbon (12.0/44.0) x 100 = 27.3% carbon

Practice problems What is the percentage by mass of iron in Iron(III) chloride?

Iron(III) chloride is FeCl 3. Iron has a mass of 55.8g FeCl 3 has a molecular mass of (55.8/162.3) x 100 = 34.4%

Practice problems What is the percentage by mass of oxygen in carbon monoxide?

Carbon monoxide is CO. Oxygen has a mass of 16.0g. CO has a molecular mass of 28.0g (16.0/28.0) x 100 = 57.1%

Practice problems What is the percentage by mass of chlorine in magnesium chloride?

Magnesium chloride is MgCl 2. The mass of chlorine is 35.5g, so two chlorines will have a mass of 71.0g. The mass of MgCl 2 is 95.3g. (71.0/95.3) x 100 = 74.5%