We're the Grade 11s in Mr. Doktor's chemistry 11 class.
We're in Block A, Day 1.
We are
Theresa Nguyen
Dominika Skibicki
Charles Perea
Tim Pang
This is our blog.

Stoichimetry

-Coefficients in balanced equations represent moles
-they are also conversion factors

Examples:
Q:If a 0.15 mole sample of methance(CH4) reacts with oxygen how many moles of each product are produced?
A:CH4+202-->CO2+2H2O
0.15molCH4x1molCO2/1molCH4=0.15molCO2
0.15molCH4x2molH2O/1molCH4=0.30molH2O

Q:When 2.1x10-3 mole of Aluminum Hydroxide react with Sulphuric Acid how many moles of Aluminum Sulphate are produced?
A:2Al(OH)3+3H2SO4-->6HOH+Al2(SO4)3
2.1x10-3molAl(OH)3x1Al2(SO4)3/2Al(OH)3=1.1x10-3mol

Q:How many moles of Bauxite(Aluminum Oxide)are requried to produce 1.8 mole of pure Aluminum?
A:2Al2O3-->4Al+302
1.8molAlx2molAl2O3/4molAl=0.90mol Al2O3





Converting to mass requries one additional step

Examples:
Q:How many grams of Bauxite are required to produce 3.5 mole of Aluminum?
A:3.5molAlx2Al2O3/4Al=1.75mol of Al2O3
1.75molx102g/1mol=178.5g=1.8x10^2g(S.F.)

Q:How many grams of water are produced if 0.84mol of phosphoric acid is neutralized by Barium hydroxide?
A:2H3PO4+3BaOH2-->6HOH+Ba3(PO4)2
0.84molH3PO4x6molHOH/2H3PO4x18.0g/1mol=45.4g=45g

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