For each question, choose answer "e" if no correct answer is found.
 
 

The number of atoms contained in 9.0 grams of Be would be the same as the number of molecules contained in _____ grams of CO. a. 9.0 b. 15.6 c. 28.0 d. 33.1	The formula mass of ammonium phosphate, (NH4)3PO4, is: a. 113 amu b. 149 amu c. 303 amu d. 434 amu
The mass percentage of N in the compound N2F4 is a. 26.9% b. 28.0% c. 33.3% d. 36.5%	In which of the following samples will the mass percentage H be the greatest? a. 10.0 g C6H14 b. 20.0 g C6H14 c. 30.0 g C6H14 d. all samples have the same mass percentage H
Which of the following statements concerning the numerical value 6.02 x 1023 is incorrect? a. it is called Avogadro's number b. it denotes the number of molecules in one mole of any molecular compound c. it is the mass, in grams, of one mole of any substance d. it denotes the number of atoms in one mole of any element, if the element is in atomic form	Avogadro's number of phosphorus (P) atoms would have a mass of a. 6.02 x 1023 g b. 6.02 x 10-23 g c. 15.0 g d. 31.0 g
Which of the following statements about "oneself mole of H2O" is incorrect? a. it contains the same number of molecules as oneself mole of CCl4 b. it has the same mass, in grams, as oneself mole of CCl4 c. it contains 3.01 x 1023 molecules d. it has a mass of 9.0 grams	According to the law of definite proportions, if a sample of a compound contains 10.0 grams of sulfur and 5.0 grams of oxygen, then another sample of the same compound which contains 20.0 grams of sulfur must contain a. 10.0 g of oxygen b. 5.0 g of oxygen c. 2.5 g of oxygen d. 1.0 g of oxygen
An atom of an element has a mass of 1.792 x 10-22 grams. What is the atomic mass of the element? a. 63.54 amu b. 107.9 amu c. 179.2 amu d. 195.1 amu	A 2.00 mole sample of the compound Mg3N2 contains a. 6.00 moles of Mg atoms b. 2.00 moles of N atoms c. 2.00 grams of Mg3N2 d. 12.04 atoms of Mg
How many atoms in 9.0 grams of silver? a. one b. 5.4 x1024 c. 5.0 x 1022 d. 5.8 x 1026	The number of moles of S in 27 g of S2Cl2 is a. 13 moles b. 6.4 moles c. 0.40 moles d. 0.20 moles
How many molecules of CO2 are present in 13.4 g of CO2? a. 5.06 x 1021 b. 1.83 x 1023 c. 9.79 x 1024 d. 3.55 x 1026	How many grams of oxygen are present in 66.2 grams of HNO3? a. 5.60 g b. 16.8 g c. 47.3 g d. 50.4 g
How many atoms are present in 4.13 moles of P4O10? a. 1.78 x 1023 atoms b. 2.49 x 1024 atoms c. 2.49 x 1025 atoms d. 3.48 x 1025 atoms	The empirical formula of a compound is CH and its formula weight is 78 amu. What is the molecular formula? a. C2H2 b. C3H3 c. C6H6 d. C8H8
What is the empirical formula of a compound that contains 45.5% Ni and 54.5% Cl? a. NiCl b. Ni4Cl5 c. NiCl3 d. NiCl2	Analysis of a sample of a compound shows that 2.50 moles of C, 3.25 moles of H and 1.00 mole of O are present. What is the empirical formula of the compound? a. C2H3O b. C3H3O c. C5H7O2 d. C10H13O4
If a 0.48 gram sample of a carbon-containing compound is burned in air, 0.44 gram of CO2 is produced. What is the percent carbon in the compound? a. 12% b. 25% c. 55% d. 92%	What is the mass in GRAMS of one atom of mercury? a. 1.2 x 10-22 b. 3.3 x 10-22 c. 1.2 x10-23 d. 1.6 x 10-24