FORMULAS, EQUATIONS AND MOLES Chemical Equation Stoichiometry Chemical Formula.
Chapter 9 moles, equations, and stoichiometry
Transcript of Chapter 9 moles, equations, and stoichiometry
Moles, Equations, and Stoichiometry
Moles Atoms
• How many sucrose molecules do you have if the beaker contains 3.5 moles?
Hint:How many bagels do you have in 3.5 dozen?
2.107 x 1024
1.How many molecules in 0.36 mol of water?
2.How many atoms are in 1.14 mol SO3?
Atoms Moles
• If you have 5.75 x 1024 atoms of Copper, how many moles do you have?
9.55 moles
1.How many moles is 2.8 x 1024 atoms of silicon?
2.How many moles is 3.7 x 1024 molecules of CO2?
Balanced Equation
N2 + H2 → NH3
N2 + 3H2 → 2 NH3
Balanced Equation
N2 + 3H2 → 2 NH3
• Number of atoms• Number of molecules• Number of moles
Mole ratio
• N2 + 3H2 → 2NH3
• conversion factor derived from the coefficients of a balanced equation
• N2 + 3H2 → 2NH3
• If you have 7 moles of H2 and you want to know how much NH3
–What would you do?
Chemical Reactions???Lets Start Over!
• What is a Chemical Reaction?• What is all this math really about?
Chemical Reaction
• Combustion
Magnesium Oxide
1 Mg + 1 O 1 MgO
Mg + O MgO
12Mg + 12O 12MgO
mol Mg + mol O mol MgO
Chemical Reaction
• Combustion
2mol C2H2 + 5 mol O2 4 mol CO2 + 2 mol H20
Avogadro’s Number
6.02 × 1023
• Number of atoms in 12 grams of Carbon-12
Molar Mass
The mass of 1 mole of a substance
Molar MassUsing the Periodic Table
N2 + 3H2 → 2 NH3
• mass of 1 mol of N2 =
28 g• mass of 3 mol of H2 =
6 g• mass of 2 mol of NH3 =
34 g
• If you find the mass of a sample of glucose (C6H12O6) to be 90.0 g, how many moles of glucose do you have?
• A certain laboratory procedure requires the use of 0.100 moles of magnesium. How many grams of magnesium would you mass out on the balance?
2 step problem
• What would be the mass of 3.75 x 1021 atoms of iron?• First change number of atoms to moles• Now, change number of moles to mass