Percent Comp.
Given: SrO
Wanted: percent composition?
Sr=84.6%
O=15.4%
What is the empirical formula of a compound that is 63.59% N, 9.15% H and 27.26% C?
N2H4C
____ Mn (s) + ____ HBr (aq) → ____ MnBr2 (aq) + ____ H2 (g)
Mn+HBr --> MnBr2+H2
HI + Sr(OH)2 → SrI2 + H2O
If 300 grams of Sr(OH)2 are reacted with 1.6 grams of HI, how many grams of SrI2 will be produced?
2.14 g SrI2 is produced
LR=HI
What is a synthesis reaction?
Two or more reactants combine to form one product.
Given: SrC2O4
Wanted: percent composition?
Sr=49.9%
C=13.7%
O=36.4%
What is the empirical formula of a compound that is 22.98% Sn, 27.45% Cl and 49.56% O?
SnCl4O16 OR Sn(ClO4)4
____ copper (II) chloride + ____ sodium sulfide → ____ copper (II) sulfide + ____ sodium chloride
CuCl2+Na2S -->CuS+2NaCl
1 mol hydroiodic acid + 1 mol lithium hydroxide →
1 mol lithium iodide + 1 mol water
If 346.1 grams of hydroiodic acid (HI) are reacted with 2.213 × 1021 particles of lithium hydroxide, what is the limiting reactant?
LR is LiOH
Name each of the state symbols listed below:
(s), (l), (g), (aq.)*
What does (aq.) mean?
solid, liquid, gas, & aqueous
(aq.) means it dissolves in water
A compound is analyzed in the lab and is found to be composed of 63.29 g lead and 5.71 g nitrogen. What is the percent composition by mass of each element in this compound?
Pb=91.7%
N=8.3%
A chemical compound is analyzed in the lab and the results suggest that it's made of 82.04 g Ba, 16.73 g N and 38.23 g O. What is the empirical formula of this compound?
BaN2O4
Given: 8.15 mol CuMnO4
Wanted: particles?
4.91*1024 particles
2 P + 3 Cl2 → 2 PCl3
If 2.1 moles of Cl2 are reacted with 6.7 × 1024 particles of P, how many moles of PCl3 will be produced?
1.4 mol PCl3
LR=Cl2
What is percent composition?
Express what percent of mass is made up of each constituent (element) of the compound
Given:
• 124.33 g barium
• 18.70 g phosphorus
• 28.97 g oxygen
Wanted: percent composition?
Ba=72.3%
P=10.9%
O=16.8%
In the lab, a substance is experimentally determined to be 133.82 g Be and 89.18 g C. What is the empirical formula of this compound?
Be2C
25g H2SO4 → ________ Oxygen Atoms
6.14 * 1023 Oxygen atoms
1 mol iron (III) oxide + 3 mol carbon →
3 mol carbon monoxide + 2 mol iron
If 3.9 × 1025 particles of iron (III) oxide are reacted with 9.3 moles of carbon, how many grams of iron will be produced?
346.27 g Fe
LR=C
What is empirical formula?
Shows simplest whole-number ratio and the relationship between different elements in a chemical formula
What is the percent composition by mass of each element in XeF4?
Xe=63.3%
F=36.7%
Vitamin C (ascorbic acid) contains 40.92 % C, 4.58 % H, and 54.50 % O, by mass. The experimentally determined molecular mass is 176 g/mol. What are the empirical and chemical formulas for ascorbic acid?
Empirical: C3H4O3
Molecular:C6H8O6
4 mol iron (II) chloride + 3 mol oxygen gas →
2 mol iron (III) oxide + 4 mol chlorine gas
If 300 grams of iron (II) chloride are reacted, how many moles of oxygen gas will also be reacted?
1.76 mol O2
Pb(NO3)2 + H2SO4 → PbSO4 + 2 HNO3
If 9.9531022 particles of H2SO4 are reacted with 1.964 moles of Pb(NO3)2, how many grams of PbSO4 will be produced? What is the LR?
Produced 50.12 g PbSO4
LR=H2SO4
What are the 4 steps to balancing an equation?
Write the skeleton equation
Count the atoms on both sides of the reaction. Polyatomic ions are counted as a group ONLY if its present on BOTH sides
Balance the equations by adding coefficients to make the number of atoms on both sides the same
CHECK YOUR WORK BY COUNTING EACH ELEMENT TO MAKE SURE THEY’RE EVEN ON BOTH SIDES