Calculating Percent Error

Slides:



Advertisements
Similar presentations
Calculating Percent Error. What is it?? Percent Error is used to determine the inaccuracy, in percentage, of a measured or estimated value, compared to.
Advertisements

Calculating Empirical and Molecular Formulas
Accuracy, Precision, Percent Error, & Temperature Scales.
Homework Check Find the percent composition of the following: 1. A compound with g of Na and 77.4 g of O 2. Ammonium Nitrate (NH 4 NO 3 ) 3. Ca(C.
Empirical and Molecular Formulas
Molar Mass & Percent Composition
Percent Composition. What is Percent Composition?  The percent composition by mass of a compound represents the percent that each element in a compound.
Empirical Formula The empirical formula indicates the ratio of the atoms of an element in a compound.
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.
1 Chapter 12 Chemical Quantities. 2 How do you measure things? How do you measure things? n We measure mass in grams. n We measure volume in liters. n.
Stoichiometry Chapter 8. Stoichiometry Chemical equations Limiting reagent Problem types Percent yield Mass-mass Mole - mole other.
Choose Your Category The MoleAverage Atomic Mass and Molar Mass FormulasPercentage Composition Limiting Reactants Percentage Yield and Error Vocab 100.
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.
IIIIII C. Johannesson III. Formula Calculations (p ) Ch. 3 & 7 – The Mole.
Percent Composition Like all percents: Part x 100 % whole Find the mass of each component, divide by the total mass.
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!
% by Mass Another way to measure the concentration of a solution % by mass = mass solute x 100 mass solution Solution = solute + solvent.
Unit 2 Unit 2 Percent Error We know that measurements can be described in terms of precision (how close a group of measurements are to each other) and.
Section 10.3 Percent Composition and Chemical Formulas.
IIIIII III. Formula Calculations (p ) Ch. 3 & 7 – The Mole.
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.
Empirical Formula vs. Molecular Formula Empirical formula: the formula for a compound with the smallest whole-number mole ratio of the elements Molecular.
IIIIII Formula Calculations The Mole. A. Percentage Composition n the percentage by mass of each element in a compound.
Percent Composition Percent by mass of an element in a compound.
Empirical & Molecular Formulas. Percent Composition Def – the percent by mass of each element in a compound Percent by mass = mass of element x 100 mass.
Moles COUNTING BY WEIGHING. Moles (is abbreviated: mol)  It is an amount, defined as the number of carbon atoms in exactly 12 grams of carbon-12.  1.
10-3: Empirical and Molecular Formulas. Percentage Composition The mass of each element in a compound, compared to the mass of the entire compound (multiplied.
PERCENT YIELD. Percent Yield Percent yield is the ratio of actual yield of an experiment to theoretical yield. To find percent yield, you divide the actual.
Section 6.3 Formulas of Compounds 1.Recognize and explain the differences between empirical and molecular formulas 2.Calculate the empirical formula of.
Actual and Percent Yields So far when we have been talking about reactions we have been talking about 100% of the (limiting) reactant becoming a product.
Percentage Composition. Percent partwhole X 100% mass of element mass of compound X 100% X 100% percent by mass =
Avogadro’s and the Mole. Moles a mole is the number of carbon atoms in exactly 12g of carbon. a mole is a unit of measurement, just like grams…
2.4 Measurement and Significant Figures Every experimental measurement has a degree of uncertainty. The volume, V, at right is certain in the 10’s place,
Empirical Formula EQ: How is the empirical formula calculated with experimental data?
Percent Composition. What is it? Percent composition is the percent by mass of each element present in a compound.
IIIIII II. % Composition and Formula Calculations Ch. 3 – The Mole.
Grams. kilograms Brian estimated the mass of my pet llama to be 95,000 grams. When he placed it on a balance he got a reading of 49 kilograms, what was.
Calculating Percent Error
Accuracy, Precision, Percent Error, & Temperature Scales
III. Formula Calculations (p )
Calc.: Gram Formula Mass
Calculating Percent Error
EMPIRICAL FORMULA VS. MOLECULAR FORMULA .
III. Formula Calculations (p )
The Mole Formula Calculations.
Simplest Chemical formula for a compound
Calculating Percent Error
III. Formula Calculations (p )
III. Formula Calculations (p )
Molecular Formula number and type of atoms covalent compounds
Calculating Empirical and Molecular Formulas
Percent Composition, Empirical Formulas, and Molecular Formulas
Percent Composition Empirical Formula Molecular Formula
FORMULA NUMBER OF MOLES GIVEN WEIGHT MOLAR MASS = GW MM n =
II. Percent composition
Determining Empirical and Molecular Formulas
III. Formula Calculations
Moles and Formula Mass.
Calculating Average Atomic Mass
How many moles of water are made by
Calculation Of Molar Mass
II. Percent composition
III. Formula Calculations (p )
Percentage Composition
Calculating Average Atomic Mass
Average Atomic Mass.
III. Formula Calculations (p )
III. Formula Calculations (p )
The Determination of an Empirical Formula
Presentation transcript:

Calculating Percent Error

What is it?? Percent Error is used to determine the inaccuracy, in percentage, of a estimated value, compared to the actual value.

The Components of the Formula Estimated Value (Measured Value)- The educated guess of an experiment. Actual Value (What you should have gotten!)- This value is the exact value.

The formula X 100 = Percent Error The Formula for Percent Error is a follows: (The Difference) Actual Value Remember: PS. We multiply by 100 to make to make the decimal a percent. X 100 = Percent Error

Practice Problems 1.) Johnny calculates from an experiment that he has 22.7 grams of carbon. However, he should have gotten 21.8 grams of carbon, which was the actual value for this experiment. What was his percent error? Remember: (Difference) X 100 = PE Actual Value

Answer (Difference) X 100 = PE AV (22.7 - 21.8) X 100 = PE 21.8

More Practice 2.) The actual value for the absorption of carbon is 0.135. Steven calculated that absorption was 0.235. What is the percent error in Steven’s experiment?

Answer (Difference) X 100 = PE AV (.235 - .135) X 100 =PE .135

Additional practice 3.) The boiling point of water is 100°C. During an experiment, water came to a boil at 97°C according to the thermometer that was being used. What is the percent error of the thermometer? answer 3.0%

Additional practice 4.) An experiment was conducted to find the mass of one mole of carbon atoms. The results of the experiment showed that a mole of carbon atoms had a mass of 15.78 g. The actual value of a mole of carbon atoms is 16.00 grams. What is the percent error in this experiment? answer 1.4%

Additional practice 5.) An experiment performed to determine the density of lead yields a value of 10.95 g. The actual value for the density of lead is 11.34 g. Find the percent error. answer 3.4%