3NO2 + H20 --> 2HNO3 + NO
How many grams of nitrogen dioxide are required in this reaction to produce 5.00 g HNO3
What is 5.48
100
How many moles of sodium atoms correspond to 1.56x1021 atoms of sodium?
What is 2.59x10-3mol Na atoms
100
How many grams of O are combined with 7.14x1021 atoms of N in the compound N2O5?
What is 0.474g O
100
Ca(OH)2 + HCl à CaCl2 + H2O
What is Ca(OH)2 + 2HCl à CaCl2 + 2H2O
100
What is a mole?
aAchemical mass unit, defined to be 6.022 x 1023 molecules, atoms, or some other unit. The mass of a mole is the gram formula mass of a substance.
200
2N2O5 --> 4NO2 + O2
If a sample of N2O5 produces 1.618 g of O2, how many grams of NO2 are formed?
What is 9.304
200
How many moles of Al atoms are needed to combine with 1.58 mol of O atoms to make aluminum oxide, Al2O3?
What is 1.05mol Al
200
Quantitative analysis of a sample of sodium pertechnetate with a mass of 0.896g found 0.111g Na and 0.477g technetium (Tc). The remainder was oxygen. Calculate the empirical formula of sodium pertechnetate, NaxTcyOz.
What is NaTcO4
200
AgNO3 + CaCl2 à Ca(NO3)2 +AgCl
What is 2AgNO3 + CaCl2 à Ca(NO3)2 + 2AgCl
200
What is molar mass?
Weight of chemical mole: the weight of one mole of any chemical substance.
300
4KO2 + 2H2O --> 4KOH + 3O2
If the reaction has .15 mole of KO2and .10 mol H2, how many moles of oxygen can be produced?
What is 0.11
300
How many moles of Al are in 2.16 mol of Al2O3?
What is 4.32mol Al
300
A substance was found to be composed of 22.9% Na, 21.5% B, and 55.7% O. What is the empirical formula of this compound?
What is Na2B4O7
300
Fe2O3 + C à Fe + CO3
What is 2Fe2O3 + 3C à 4Fe + 3CO3
300
What is stoichiometry?
It is the accounting, or math, behind chemistry. Given enough information, one can use stoichiometry to calculate masses, moles, and percents.
400
CO + 2H2 --> CH3OH
If the reaction has 35.4 g of CO and 10.2 g of H2 how many grams of CH3OH will be produced?
What is 40.5
400
What is the total number of atoms in 0.260 mol of glucose, C6H12O6?
What is 3.76x1024 atoms
400
When 0.684 g of an organic compound containing only C, H, and O was burned in oxygen 1.312g CO2 and 0.805g H2O were obtained. What is the empirical formula of the compound?
What is C2H6O
400
NaHCO3 + H2SO4 à Na2SO4 + H2O + CO2
What is 2NaHCO3 + H2SO4 à Na2SO4 + 2H2O + 2CO2
400
What is a catalyst?
A chemical substance placed into a reaction to speed up the time it takes for the reaction to occur. It is not consumed in the reaction.
500
What is the mass of 1.00 mol of each of the following elements?
a. Sodium
b. Sulfur
c. Chlorine
What is a. 23.0g Na b. 32.1g S c. 35.3g Cl
500
How many moles of H2 and N2 can be formed by the decomposition of 0.145 mol of ammonia, NH3?
What is 0.0725mol N2 and 0.218mol H2
500
Calculate the percentage composition by mass of each element in the following compounds:
a. NaH2PO4
b. NH4H2PO4
c. (CH3)2CO
What is
a. 19.2% Na, 1.68% H, 25.8% P, 53.3% O
b. 12.2% N, 5.26% H, 26.9% P, 55.6%O
c. 62.0% C, 10.4% H, 27.6% O