Answer:
grams H₂O produced = 8.7 grams
Explanation:
Given 2C₂H₆(g) + 7O₂(g) => 4CO₂(g) + 6H₂O(l)
7g 18g ?g
Plan => Convert gms to moles => determine Limiting reactant => solve for moles water => convert moles water to grams water
Moles Reactants
moles C₂H₆ = 7g/30g/mol = 0.233mol
moles O₂ = 18g/32g/mol = 0.563mol
Limiting Reactant => (Test for Limiting Reactant) Divide mole value by respective coefficient of balanced equation; the smaller number is the limiting reactant.
moles C₂H₆/2 = 0.233/2 = 0.12
moles O₂/7 = 0.08
<u><em>Limiting Reactant is O₂</em></u>
Moles and Grams of H₂O:
Use Limiting Reactant moles (not division value) to calculate moles of H₂O.
moles H₂O = 6/7(moles O₂) = 6/7(0.562) moles H₂O = 0.482 mole H₂O yield
grams H₂O = (0.482mol)(18g·mol⁻¹) = 8.7 grams H₂O
Mass is equal to moles x molar mass, and the molar mass of C6H12 is 84, therefore the mass is 436.8 g, but 437 rounded to correct significant figures
Answer: B. 4 moles Fe and 3 moles CO2
Explanation:
write a balanced chemical reaction
that is FeO3 + 3 CO → 2 Fe + 3CO2
2 moles of Fe2O3 reacted with 3 x2=6 moles of Co to form Fe and CO2 therefore CO was in excess and Fe2O3 was limiting reagent.
use the mole ratio to determine the moles of each product.
that is the mole ratio 0f Fe2O3 : Fe is 1:2 therefore the moles of Fe = 2x2=4 moles
the mole ratio of Fe2CO3 : CO2 is 1: 3 therefore the moles of Co2 = 2 x3 = 6 moles
Answer:
Lithium,Sodium,Potassium all belong to transition metals
