Chemistry: Molecular Nature of Matter and Change, 6th Edition (Silberberg)

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1			How many phosphorus atoms are there in 2.57 g of this element?
			A)	4.99 x 1022 atoms
			B)	4.80 x 1025 atoms
			C)	7.26 x 1024 atoms
			D)	0.0829 atoms
			E)	2.57 atoms
2			What is the mass of 5.45 x 10-3 mol of glucose C6H12O6?
			A)	0.158 g
			B)	981 g
			C)	3.03 x 10-5 g
			D)	0.981 g
			E)	none of the above
3			A 20.0 mL sample of an element with a density of 3.0 g/mL contains 4 x 1023 atoms. What is the atomic weight of this element?
			A)	300
			B)	40
			C)	60
			D)	90
			E)	none of the above
4			The mass percent nitrogen in nitrous acid, HNO2, is
			A)	7%
			B)	14%
			C)	30%
			D)	45%
			E)	60%
5			A pure sample of a new chemical compound was analyzed and was found to have the following mass percentages: Al 31.5 %; O 56.1 %; S 12.4 %. What is the empirical formula of this compound?
			A)	Al5O28S7
			B)	Al3O9S
			C)	AlO2S2
			D)	Al4O14S7
			E)	AlO6S1.5
6			The molecular formula for a compound with a molar mass of 41.5 g/mol that is 78.2% B and 21.8% H is
			A)	B3H9
			B)	B2H2
			C)	BH3
			D)	B4H4
			E)	B2H6
7			What is the sum of the four coefficients when the following equation is balanced? Equation: CS2 + CaO → CO2 + CaS
			A)	5
			B)	6
			C)	8
			D)	10
			E)	11
8			Balance the second step of the Ostwald process to determine the three coefficients. Equation: NO + O2 → NO2
			A)	1, 1, 1, respectively
			B)	2, 1, 2
			C)	2, 5/2, 2
			D)	4, 5, 4
			E)	none of the above
9			How many moles of oxygen gas will react with 12.4 mol aluminum? Equation: 4Al + 3O2 → 2Al2O3
			A)	0.24 mol
			B)	0.42 mol
			C)	4.8 mol
			D)	9.3 mol
			E)	16.8 mol
10			In the reaction of Fe3O4 with carbon to form carbon dioxide and iron, the number of moles of carbon required to convert 23 g of Fe3O4 to products is
			A)	0.05
			B)	0.1
			C)	0.2
			D)	0.3
			E)	0.4
11			Hydrogen chloride can be prepared by the reaction shown below: 2NaCl(s) + H2SO4(l) → 2HCl(g) + Na2SO4(s) How many grams of HCl can be prepared from 393 g H2SO4 and 4.00 moles NaCl?
			A)	293 g
			B)	1.003 g
			C)	786 g
			D)	146 g
			E)	393 g
12			What is the percent yield of PI3, if 58.62 g of I2 are reacted with an excess of phosphorus and 60.75 g of PI3 are actually obtained? Equation: 2P(s) + 3I2(s) → 2PI3(s)
			A)	84.97 %
			B)	1.57 %
			C)	48.37 %
			D)	37.6 %
			E)	95.8 %
13			What is the molar concentration of a solution containing 22.0 g of CH3OH in 250 cm3 of solution?
			A)	3.17 M
			B)	0.088 M
			C)	8.80 M
			D)	2.75 M
			E)	4.25 M
14			Approximately how many mL of water must be added to 300 mL of 0.75 M HCl to dilute the solution to 0.25 M?
			A)	900 mL
			B)	600 mL
			C)	300 mL
			D)	930 mL
			E)	100 mL
15			How many grams of NaH2PO4 are needed to react completely with 57.48 mL of 0.225 M NaOH? The molar mass of NaH2PO4 is 119.98 g/mol. Equation: NaH2PO4(s) + 2NaOH(aq) → Na3PO4(aq) + 2H2O(l)
			A)	38.80 g
			B)	0.776 g
			C)	0.388 g
			D)	7.766 g
			E)	0.194 g