Week 11 Friday
Now that we have put a coefficient of 3 in front of CaSO4, what coefficient should go in front of CaCl2 to balance calcium (Ca )? 3CaSO4+AlCl3→?CaCl2+Al2(SO4)3
3
Solid potassium chlorate (KClO3) decomposes into potassium chloride and oxygen gas when heated. How many moles of oxygen form when 46.1 g completely decomposes?
0.564 mol O2 Write a balanced chemical equation: 2KClO3(s)⟶Δ2KCl(s)+3O2(g) Then convert the mass of KClO3 to moles of KClO3 before using the stoichiometric conversion factors to convert to moles of O2 . 46.1gKClO3 ×1molKClO3122.55gKClO3×3molO22molKClO3=0.564molO2
What are the correct coefficients (reading from left to right) when the chemical equation is balanced? __PCl3(l)+__H2O(l)→__H3PO3(aq)+__HCl(aq)
1, 3, 1, 3 Start by placing a 1 in front of PCl3, then a 1 in front of H3PO3 to balance the P atoms. Balance Cl atoms by placing a 3 in front of HCl; finally balance the O atoms by placing a 3 in front of H2O. This set of coefficients results in the same number of each type of atom on both sides of the equation. There are one P atom, three Cl atoms, six H atoms, and three O atoms on each side of the equation.
When methane (CH4 ) burns, it reacts with oxygen gas to produce carbon dioxide and water. The unbalanced equation for this reaction is CH4(g)+O2(g)→CO2(g)+H2O(g) This type of reaction is referred to as a complete combustion reaction. What coefficients are needed to balance the equation for the complete combustion of methane? Enter the coefficients in the order CH4, O2, CO2, and H2O, respectively.
1,2,1,2
Sulfuric acid dissolves aluminum metal according to the following reaction: 2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g) Suppose you wanted to dissolve an aluminum block with a mass of 14.8 g . What minimum mass of H2SO4 would you need? What mass of H2 gas would be produced by the complete reaction of the aluminum block?
1.65 g
An important reaction that takes place in a blast furnace during the production of iron is the formation of iron metal and CO2 from Fe2O3 and CO. Find the mass of CO2 that forms in this process.
1048 kg
Manganese(IV) oxide reacts with aluminum to form elemental manganese and aluminum oxide: 3MnO2+4Al→3Mn+2Al2O3 What mass of Al is required to completely react with 28.0 g MnO2?
11.6 g Al Convert the mass of MnO2 to moles and then use the stoichiometric ratio to convert to moles of Al; and finally, convert the moles of Al to mass. 28.0gMnO2×1molMnO286.94gMnO2×4molAl3molMnO2×26.98gAl1molAl=11.6gAl
The balanced chemical equation for the combustion of propane is C3H8(g)+5O2(g)→3CO2(g)+4H2O(g) Which statement is correct about the complete combustion of 3.00 mole of propane, C3H8?
12.00 mol H2O are produced. You often see amounts reported by mass, in the base unit grams. To use the balanced chemical equation to predict quantities, first the mass must be converted to moles using the molar mass of the species. After making all comparisons in moles, the quantity can be converted back to mass for easier measurement and reporting.
An important reaction that takes place in a blast furnace during the production of iron is the formation of iron metal and CO2 from Fe2O3 and CO. Find the mass of Fe2O3 required to form 890 kg of iron.
1270 kg
Now that we have put coefficients of 3 in front of CaSO4 and CaCl2, what coefficient should go in front of AlCl3 to balance both the Cl atoms and the Al atoms? 3CaSO4+?AlCl3→3CaCl2+Al2(SO4)3
2
Notice that "SO4" appears in two different places in this chemical equation. SO42− is a polyatomic ion called "sulfate." What number should be placed in front of CaSO4 to give the same total number of sulfate ions on each side of the equation? ?CaSO4+AlCl3→CaCl2+Al2(SO4)3
3
Sulfuric acid dissolves aluminum metal according to the following reaction: 2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g) Suppose you wanted to dissolve an aluminum block with a mass of 14.8 g . What minimum mass of H2SO4 would you need?
80.7 g
The basic principle in balancing a chemical equation is to ______.
have the same number of atoms of each element in the reactants and in the products
