Conversions
How do you convert from moles to grams?
30 seconds
Multiply by molar mass
Explain what Avogadro's Number describes
30 seconds
How many particles per mole of any element
What does molarity describe AND what units is molarity in?
30 seconds
Concentration of a solution. moles/liter
How do you find the empirical formula of a compound given the percent of each element in the formula?
30 seconds
Assume 100 g total, go from g to mol, divide each mole amount by the smallest number of moles.
What is the limiting reagent of a reaction?
30 seconds
The reactant that produces the lowest amount of product (limits the reaction)
If you have a 10 g sample of C, N, O and F, which has the most atoms?
30 seconds
C
How many water molecules are in 0.82 moles of water?
1 minute
4.9 x 1023 molecules
What is the molarity of the solution that has 2.0 mol NaCl in 0.872 L of solution?
30 seconds
2.3 M
What is the percent composition of each element in HNO3?
2 minutes
1.6% H, 22.2% N, 76.2% O
What is the formula for percent yield, including units?
30 seconds
Percent yield = actual yield (g) / theoretical yield (g) x 100%
How many grams are in 2.6 mol of lithium?
1 minute
18 g Li
How many moles of CO2 are in 65 g CO2?
1 minute
1.5 mol
How many grams of solute are in the solution that has 671 mL of 2.0 M NaOH?
2 minutes
54 g NaOH
What is the empirical formula for a substance that is 32.4% Na, 22.6% S, and 45% O?
2 minutes
Na2SO4
2 Na + 2 H2O --> 2 NaOH + H2
What is the limiting reagent of this reaction if 25 g of sodium and 40.2 g of water are present? How many grams of NaOH does it produce?
2 minutes
Na, 43.5 g NaOH
A 1.45 g sample of carbon contains how many atoms?
2 minutes
7.28 x 1022 atoms
How many atoms are present in 5.00 grams of iron?
2 minutes
5.39 x 1022 atoms
Balance the equation:
CoCl2 + ClF3 --> CoF3 + Cl2
2 minutes
2 CoCl2 + 2 ClF3 --> 2 CoF3 + 3 Cl2
Given the reaction: 2 H2O --> 2 H2 + O2
How many moles of hydrogen gas result from the electrolysis of 78.4 mol water?
2 minutes
78.4 mol H2
Fe2O3 + 3 CO --> 2 Fe + 3 CO2
What is the limiting reagent if 50 g Fe2O3 and 67 g CO are present and how many grams of Fe does it produce?
2 minutes
Fe2O3, 34.97 g
What mass of chlorine is present in 5.00 grams of CCl4, carbon tetrachloride?
2 minutes
4.61 g Cl
5 g CCl4 x 141.8 g Cl4 / 153.8 g CCl4
How many hydrogen atoms are present in 1.0 g of NH3?
2 minutes
1.1 x 1023 atoms
1.0 g NH3 x 1 mol / 17 g NH3 x 6.022 x 1023 atoms / 1 mol x 3 (3 H's in NH3)
Balance the equation:
NH3 + F2 --> N2 + HF
2 minutes
2 NH3 + 3 F2 --> N2 + 6 HF
Consider the reaction: 4 Fe + 3 O2 --> 2 Fe2O3
How many grams of rust (Fe2O3) would form if we started with 20.0 moles of iron with excess oxygen?
2 minutes
1.60 x 103 g
SO2 + H2O --> H2SO3
What is the percent yield if 19.07 g of SO2 reacts with excess water to produce 21.61 g H2SO3?
2 minutes
88.46%