Chemistry

Give the correct number of significant figures to the problem below. 5.80 x 10-1 - 3.4 x 10-2 = A) 5.5 x 10-1 B) 5.46 x 10-1 C) 2.4 x 10-3 D) 2.4 x 102 E) 5.5 x 10-2

5.80 x 10-1 - 3.4 x 10-1 = B) 5.46 x 10-1

A block of iron has a mass of 483 g. What is the mass of a block of graphite that has the same volume as the block of iron? The following densities at 25°C are provided: magnesium, 1.7 g/cm3 ; graphite, 1.8 g/cm3 ; iron, 7.9 g/cm3. A) 110 g B) 2120 g C) 6870 g D) 34 g E) none of them are within 10 g of the right answer

A block of iron has a mass of 483 g. What is the mass of a block of graphite that has the same volume as the block of iron? The following densities at 25°C are provided: magnesium, 1.7 g/cm3 ; graphite, 1.8 g/cm3 ; iron, 7.9 g/cm3. A) 110 g B) 2120 g C) 6870 g D) 34 g E) none of them are within 10 g of the right answer

If the price of gasoline is $3.85 per U.S. gallon, what is the cost per liter? (1 L = 1.06 qt) A) $1.02/L B) $14.60/L C) $0.96/L D) $3.85/L E) $3.63/L

A) $1.02/L

The density of mercury is 13.6 g/cm3. What is the mass in pounds of 1.0 gallons of mercury? (1 lb = 453.6 g; 1 gal = 3.785 L)

A) 0.11 lb B) 30. lb C) 51 lb D) 83 lb E) 110 lb

Calculate the number of moles of cesium in 50.0 g of cesium. A) 0.376 mol B) 0.357 mol C) 2.66 mol D) 2.80 mol E) 0.0200 mol

A) 0.376 mol same concept

The average distance from Earth to the sun is 9.3 × 107 miles. How many kilometers is this? A) 1.5 × 108 km D) 1.7 × 10-8 km B) 1.5 × 105 km E) 1.5 × 1011 km C) 5.6 × 107 km

A) 1.5 × 108 km

How many Br atoms are in 2.50 g of Br? A) 1.88x1022 Br atoms D) 6.02 x 1023 Br atoms B) 1.51 x 1024 Br atoms E) 9.42 x 1021 Br atoms C) 7.54 x 1021 Br atoms

A) 1.88x1022 Br atoms 2.50/79.90 x 6.022x10^23

Complete the following chart, in order from left to right N^14

A) 14, 7, 7, 7 D) 7, 14, 7, 7 B) 14, 7, 14, 7 E) Some other answer C) 7, 7, 7, 7

9. Which of the following are isotopes? A) 14C and 13C D) 12C and 12CO B) 14C and 14N E) 14N and 14N2 C) 14N and 14N3-

A) 14C and 13C

What is the molar mass of acetaminophen, C8H9NO2? A) 151.16 g/mol D) 143.10 g/mol B) 43.03 g/mol E) 135.16 g/mol C) 67.09 g/mol

A) 151.16 g/

Calculate the molecular mass of menthol, C10H20O. A) 156.26 amu D) 48.17 amu B) 140.26 amu E) 137.11 amu C) 29.02 amu

A) 156.26 amu

What is the average mass of one Ca atom? A) 40.08 amu D) 2.41 x 10-21 amu B) 40.08 g E) 2.41x1025 g C) 40.08 g/mol

A) 40.08 amu

Complete the following chart, in order from left to right

A) 40Zr, 21 B) 19K, 40 C) 21K, 19 D) 40K, 21 E) 38Sr, 19

Convert 4.5 x 104 to decimal format. A) 45,000 B) 4,500 C) 0.00045 D) 0.0045 E) 0.000450

A) 45,000

An average atom of uranium (U) is approximately how many times heavier than an atom of potassium? A) 6.1 times B) 4.8 times C) 2.4 times D) 12.5 times E) 7.7 times

A) 6.1 times

How many moles of C are in 1.22 moles of C6H12O6? A) 7.32 moles C D) 14.7 moles C B) 87.9 moles C E) 2.44 moles C C) 1.22 moles C

A) 7.32 moles 1.22 times by 6

Which one of the following is an ion? A) B3+ B) NaCl C) He D) 14C E) none of the above

A) B3+

What is the formula for the ionic compound containing barium ions and sulfate ions? A) BaSO4 B) Ba2SO4 C) BaS D) Ba(SO4)2 E) Ba3S2

A) BaSO4

An organic thiol compound is 38.66% C, 9.73% H, and 51.61% S by mass. What is the empirical formula of this compound? A) C2H6S B) C3H8S C) C4H10S D) C4H12S E) C5H14S

A) C2H6S same format 38.66/12=2 9.73/1.008=6 51.61/32.07 c2h6s

Which one of the following does not represent 1.000 mol of the indicated substance? A) 6.022 × 1023 C atoms D) 65.39 g Zn B) 26.00 g Fe E) 6.022 × 1023 Fe atoms C) 12.01 g C

B) 26.00 g Fe

section 3.5 The mineral orpiment, having the empirical formula As2S3, was used in ancient times as a cosmetic. What mass of arsenic is present in 5.0 g of orpiment? [Given: naturally occurring arsenic is all arsenic-75; assume that all naturally occurring sulfur is sulfur-32 (only approximately true)] A) 0.61 g B) 3.0 g C) 1.5 g D) 2.0 g E) 3.5 g

B) 3.0 g

Determine the number of moles of aluminum in 96.7 g of Al. A) 0.279 mol Determine the number of moles of aluminum in 96.7 g of Al. A) 0.279 mol B) 3.58 mol C) 7.43 mol D) 4.21 mol E) 6.02 × 1023 C) 7.43 mol D) 4.21 mol E) 6.02 × 1023

B) 3.58 mol 96.7 g of Al./26.98

What is the average mass of one S atom? A) 32.07 g D) 5.32 x 10-23 amu B) 32.07 amu E) 1.93 x 1025 g C) 32.07 g/mol

B) 32.07 amu

Chlorine gas reacts with phosphorus to produce phosphorus pentachloride. How many grams of PCl5 are produced from 3.5 g of Cl2 and excess P? 5Cl2(g) + 2P(s) = 2PCl5(s) A) 1.4 g B) 4.1 g C) 8.2 g D) 0.020 g E) 730 g

B) 4.1 g 4.5 x 1/70.90 x 2/5 x 208.23

How many moles of NH3 are there in 77.5 g of NH3? A) 0.220 mol D) 1.31 × 103 mol B) 4.55 mol E) None of the above. C) 14.0 mo

B) 4.55 mol 77.5/17

An atom of the isotope 137Ba consists of how many protons (p), neutrons (n), and electrons (e)? A) 56 p, 137 n, 56 e D) 56 p, 56 n, 56 e B) 56 p, 81 n, 56 e E) 81 p, 56 n, 81 e C) 137 p, 81 n, 56 e

B) 56 p, 81 n, 56 e

A compound was discovered whose composition by mass is 85.6% C and 14.4% H. Which of the following could be the molecular formula of this compound A) CH4 B) C2H4 C) C3H4 D) C2H6 E) C3H8

B) C2H4

A compound with an empirical formula of C2H2Br3 has a molar mass of 531.47 g/mol. What is the molecular formula? A) C2H2Br3 B) C4H4Br6 C) CHBr D) C4H4Br3 E) C6H6Br9

B) C4H4Br6 multiply everthing by 2

What is the empirical formula for C10H22O2? A) C10H22O2 B) C5H11O C) C20H44O4 D) C2H11O E) C5H11O2

B) C5H11O divide the subscript by the smallest number

An unknown compound with a molar mass of 223.94 g/mol consists of 32.18% C, 4.50% H, and 63.32% Cl. Find the molecular formula for the compound. A) CHCl B) C6H10Cl4 C) C3H5Cl2 D) C9H15Cl6 E) C6H10Cl2

B) C6H10Cl4

Which of the following is an example of an empirical formula? A) C9H12 B) C9H18Cl2 C) C6H6 D) N2O4 E) C2H2O2

B) C9H18Cl2

110. Hydrogen chloride gas can be prepared by the following reaction: 2NaCl(s) + H2SO4(aq) ® 2HCl(g) + Na2SO4(s) How many grams of HCl can be prepared from 2.00 mol H2SO4 and 2.56 mol NaCl? A) 7.30 g B) 93.3 g C) 146 g D) 150 g E) 196 g

Moles NaCl = 150 g / 58.44 = 2.56 The ratio between NaCl and H2SO4 is 2 : 1 so NaCl is the limiting reactant We would get 2.56 mol HCl => 2.56 mol x 36.46 g/mol = 93.3 g

What is the coefficient of H2O when the equation below is properly balanced? ___ PCl3(l) + ___ H2O(l) = ___ H3PO3(aq) + ___ HCl(aq) A) 1 B) 2 C) 3 D) 5 E) none of these

PCl3(l) + 3 H2O(l) = H3PO3(aq) + 3 HCl(aq) ___ PCl3(l) + ___ H2O(l) = ___ H3PO3(aq) + ___ HCl(aq) C) 3

What is the mass of 0.0250 mol of P2O5 A) 35.5 g B) 5676 g C) 0.0250 g D) 1.51 × 1022 g E) 3.55 g

0.0250 mol x 141.9445 g P2O5?

What is the theoretical yield of ammonia that can be obtained from the reaction of 10.0 g of H2 and excess N2? N2 + 3H2 = 2NH3 A) 28.4 g B) 48.6 g C) 56.3 g D) 90.0 g E) 97.1 g

10/2.015=4.9627x 2nh3/3h2 x 17.03=56.3 C) 56.3

Calculate the mass of O in 4.36 g of Cl2O7? A) 30.5 g O B) 48.8 g O C) 11.2 g O D) 69.8 g O E) 2.67 g O

2.67 • Calculate the molar mass of Cl2o7 • Divide by 4.36/182.9018Cl2o7 • Times by O7 by the molar mass WHICH IS 16 X7

chapter 1 que 32 The density of lead is 11.4 g/cm3 at 25°C. Calculate the volume occupied by 25.0 g of lead. A) 2.19 cm3 B) 0.456 cm3 C) 285 cm3 D) 1.24 cm3 E) 6.05 cm3

25/114=2.19 The density of a substance is equal to the ratio of mass of substance to the volume. The formula for density is; Density = mass / volume Density = 3.12 g/ cm3 mass = 28.1 grams Volume = mass / density Volume = 28.1 grams / 3.12 grams / cm3 Volume = 9 centimeter cube

Lithium metal reacts with nitrogen gas to form lithium nitride. Identify the balanced reaction that describes this process. A) Li + N = LiN D) 6Li + N2 = 2Li3N B) Li + N2 = LiN2 E) 2Li + N2 =2LiN C) 2Li + N2 = Li2N2

6Li + N2 = 2Li3N

Iron has a density of 7.86 g/cm3. The volume occupied by 55.85 g of iron is A) 0.141 cm3 B) 7.11 cm3 C) 2.8 cm3 D) 439 cm3 E) None of the above.

7.11 mass/volume 55.85/7.86

If 0.274 moles of a substance weighs 62.5 g, what is the molar mass of the substance, in units of g/mol? A) 2.28 × 102 g/mol D) 2.17 × 102 g/mol B) 1.71 × 101 g/mol E) 6.02 x 1023 g/mol C) 4.38 × 10-3 g/mol

A) 2.28 × 102 g (62.5x1)/0.274=228.1g/mo

The Hope diamond weighs 44.0 carats. Determine the volume occupied by the diamond, given that its density is 3.5 g/cm3 at 20°C, and that 1 carat = 0.200 g. A) 2.5 cm3 B) 0.40 cm3 C) 0.016 cm3 D) 63 cm3 E) 150 cm3

A) 2.5 cm3

How many square kilometers are equivalent to 28.5 cm2? A) 2.85 × 10-9 km2 D) 2.85 × 10-4 km2 B) 2.85 × 10-6 km2 E) none of these C) 285 km2

A) 2.85 × 10-9 km2

What is the coefficient of H2SO4 when the following equation is properly balanced? ___ Ca3(PO4)2 + ___ H2SO4 ® ___ CaSO4 + ___ H3PO4 A) 3 B) 8 C) 10 D) 11 E) none of these

A) 3 __ Ca3(PO4)2 + ___ H2SO4 = ___ CaSO4 + ___ Ca3(PO4)2 + 3 H2SO4 = 3 CaSO4 + 2 H3PO4

Which of the following CO2 samples contains the greatest number of moles of CO2? A) 3.5 moles CO2 D) 5.60 g CO2 B) 3.21 x 1023 CO2 molecules E) 3.19 x 101 g CO2 C) 4.50 x 1022 CO2 molecules

A) 3.5 moles

1.572 × 108 troy oz of silver were used in the United States in 1980. How many kilograms is this? (1 troy oz = 31.1 g) A) 4.89 × 106 kg D) 4.89 x 1012 kg B) 4.89 kg E) 5.05 × 10 3 kg C) 5.05 × 10 6 kg

A) 4.89 × 106 kg

Which of the following speeds is the greatest? (1 mile = 1609 m) A) 40 mi/h D) 0.74 km/min B) 2.0 × 105 mm/min E) 400 m/min C) 40 km/h

A) 40 mi/h

Calculate the mass of 4.50 moles of Ca3PO4 A) 215 g B) 968 g C) 0.0209 g D) 87.1 g E) 392 g

Ans: B Category: Easy Section: 3.3 B) 968 g

44. Calculate the mass of 0.00456 moles of (NH4)2SO4 A) 132 g B) 3.45 x 10-5 g C) 114 g D) 0.603 g E) 0.520 g

Ans: D Category: Easy Section: 3.3 D) 0.603 g

There are two stable isotopes of chlorine: chlorine-35, with a mass of 34.968853 amu; and chlorine-37, with a mass of 36.965903. Given that the average atomic mass of a chlorine atom is 35.45 amu, which of the following statements is true? A) Chlorine contains almost exclusively 35 17Cl with very little 37 17 Cl. B) Chlorine contains more 35 17 Cl than 37 17 Cl. C) Chlorine contains roughly equal amounts of 35 17 Cl and 37 17 Cl. D) Chlorine contains more 37 17 Cl than 35 17 Cl. E) Chlorine contains almost exclusively of 37 17 Cl, with very little 35 17 Cl.

B) Chlorine contains more 35 17 Cl than 37 17 Cl.

Which is the correct formula for iron(II) phosphate? A) Fe2PO4 B) Fe3(PO4)2 C) Fe2PO3 D) Fe(PO4)2 E) Fe(PO3)2

B) Fe3(PO4)2

Chlorine gas can be made from the reaction of manganese dioxide with hydrochloric acid. MnO2(s) + 4HCl(aq) ® MnCl2(aq) + 2H2O(l) + Cl2(g) According to the above reaction, deterrmine the limiting reactant when 5.6 moles of MnO2 are reacted with 7.5 moles of HCl? A) MnO2 B) HCl C) MnCl2 D) Cl2 E) No reagent is limiting

B) HCl

Ammonia reacts with hydrochloric acid to produce ammonium chloride. Identify the balanced reaction that describes this process. A) NH4 + + HCl ® NH4Cl + H D) NH4 + + 2HCl ® NH4Cl2 B) NH3 + HCl ® NH4Cl E) NH3 + 2HCl ® NH4Cl2 C) NH3 + 2HCl ® NH4Cl + H Ans: B Category: Medium Section

B) NH3 + HCl = NH4Cl

What are the two different ions present in the compound NH4NO3? A) NH4 -, NO3 + D) NH4 3+, NO4- B) NH4 +, NO3 - E) NH4 +, NO3- C) N3-, H+, O2-

B) NH4 +, NO3 -

What are the two different ions present in the compound Na2S? A) Na2 +, S2- B) Na+, S2- C) Na2+, S2- D) Na+, S- E) Na2+, S-

B) Na+, S2-

Calculate the mass of the air contained in a room that measures 2.50 m × 5.50 m × 3.00 m (density of air = 1.29 g/dm3 at 25°C). A) 3.13 × 10 -5 g B) 32.0 kg C) 53.2 kg D) 53.2 g E) None of the above. A) 3.13 × 10 -5 g B) 32.0 kg C) 53.2 kg D) 53.2 g E) None of the above.

C) 53.2 kg

Calculate the average atomic mass of lithium using the following data: Isotope Abundance Mass 6Li 7.5 % 6.0151 amu 7Li 92.5% 7.0160 aum A) 6.51 amu B) 6.02 amu C) 6.94 amu D) 7.02 amu E) 6.50 amu

C) 6.94 amu 6Li 0.75 x 6.0151 amu+ 7Li 92.5 x 7.0160 aum =6.94

Bromine is a red liquid at 25°C. Its density is 3.12 g/cm3. What is the volume of 28.1 g of liquid bromine? A) 87.7 cm3 D) 28.1 cm3 B) 0.111 cm3 . E) None of the above C) 9.01 cm

C) 9.01 cm mass/volume

Give the number of protons (p), neutrons (n), and electrons (e) in one atom of 238U. A) 146 p, 92 n, 92 e D) 146 p, 28 n, 146 e B) 92 p, 92 n, 92 e E) 238 p, 146 n, 238 e C) 92 p, 146 n, 92e

C) 92 p, 146 n, 92e

What are the two different ions present in the compound Al(NO3)3? A) Al3+, (NO3)3 - D) Al3+, NO3 3- B) Al+, NO3 - E) Al+, (NO3)3 - C) Al3+, NO3

C) Al3+, NO3 -

What is the coefficient for O2 when the following combustion reaction of a fatty acid is properly balanced? __ C18H36O2 + __ O2 = __ CO2 + __ H2O A) 1 B) 8 C) 9 D) 26 E) 27

D) 26 C18H36O2 + __ O2 = __ CO2 + __ H2O C18H36O2 + 26 O2 = 18 CO2 + 18 H2O

Calculate the molar mass of Ba(NO3)2. A) 199.3 g/mol D) 261.3 g/mol B) 323.3 g/mol E) 398.6 g/mol C) 247.3 g/mol

D) 261.3 g/mol

What is the mass of 3.50 x 1024 Ti atoms? A) 47.9 amu B) 47.9 g C) 5.81 g D) 278 g E) 5.81 amu

D) 278

Give the correct number of significant figures to the problem below. 2.4 x 10-4 + 3.1 x 10-2 = A) 5.5 x 10-6 B) 5.5 x 10-8 C) 5.5 x 10-4 D) 3.1 x 10-2 E) 2.4 x 10-4

D) 3.1 x 10-2 2.4 x 10-2 + 3.1 x 10-2 = 3.1 x 10^-2

How many significant figures does the result of the following sum contain? 8.5201 + 1.93 A) 1 B) 2 C) 3 D) 4 E) 5

D) 4 you have to add it up n line up decimals 8.5201 1.93 =10.45 the 01 is discarded

What is the area, in square centimeters, of an 8.5 inch by 11 inch sheet of paper? A) 94 cm2 B) 240 cm2 C) 420 cm2 D) 6.0 × 102 cm2 E) 1.2 × 104 cm2

D) 6.0 × 102 cm2

A piece of a metal alloy with a mass of 114 g was placed into a graduated cylinder that contained 25.0 mL of water, raising the water level to 42.5 mL. What is the density of the metal? A) 0.154 g/cm3 D) 6.51 g/cm3 B) 0.592 g/cm3 E) 7.25 g/cm3 C) 2.68 g/cm

D) 6.51 g/cm3 m=114g v=42.5mL-25mL=17.5mL 1mL=1cm3, so v=42.5cm3-25cm3=17.5cm3 d=m/v d=114g/17.5cm3 d=6.51 g/cm3

How many moles of O are in 2.45 moles of H2CO3? A) 2.45 moles O D) 7.35 moles O B) 39.2 moles O E) 0.459 moles O C) 118 moles O

D) 7.35 moles O Times 3 by 2.45

Express 7,500 nm as picometers. A) 7.50 pm B) 75.0 pm C) 750 pm D) 7.5 × 106 pm E) 7.5 × 1012 pm

D) 7.5 × 106 pm

The density of mercury is 13.6 g/cm3. What volume (in quarts) is occupied by 100. g of Hg? (1 L = 1.06 qt) A) 144 qt B) 7.35 qt C) 7.79 qt D) 7.79 × 10-3 qt E) 1.44 × 10-4 qt

D) 7.79 × 10-3 qt

113. Calculate the mass of excess reagent remaining at the end of the reaction in which 90.0 g of SO2 are mixed with 100.0 g of O2. 2SO2 + O2 =2SO3 A) 11.5 g B) 22.5 g C) 67.5 g D) 77.5 g E) 400 g

D) 77.5 g 90/64.06 so2 x 1O2/2mol SO2 x 32O2/1mol =22.5 100-22.5=77.5 oxygen, it is the excess reagent

The reaction of 44.1 g of Cr2O3 with 35.0 g of Al produced 25.6 g of Cr. What is the percent yield for this reaction? 2Al + Cr2O3 ® Al2O3 + 2Cr D) 84.9%

D) 84.9% Cr2O3 IS THE limited reagent 44.1/151.99=29015 x 2/1cro3 x 51.99cr=301.69 2.56/301.69 =84.9

What is the volume, in cubic inches, of a brick that is 4.0 in × 2.7 in × 8.0 in? A) 15 in3 B) 51 in3 C) 78 in3 D) 87 in3 E) 150 in3

D) 87 in3 multiply everthing

How many O atoms are there in 51.4 g CaSO4? A) 4.00 B) 2.40 × 1024 C) 1.13 D) 9.09 × 1023 E) 2.28 × 1023

D) 9.09 × 10^23 same concept

How many Cl atoms are in 0.0728 g of PCl3? A) 4.38 x 1022 Cl atoms D) 9.58 x 1020 Cl atoms B) 1.32 x 1023 Cl atoms E) 1.81 x 1024 Cl atoms C) 3.19 x 1020 Cl atoms

D) 9.58 x 1020 Cl atom

Boron obtained from borax deposits in Death Valley consists of two isotopes. They are boron-10 and boron-11 with atomic masses of 10.013 amu and 11.009 amu, respectively. The atomic mass of boron is 10.81 amu (see periodic table). Which isotope of boron is more abundant, boron-10 or boron-11? A) Cannot be determined from data given B) Neither, their abundances are the same. C) Boron-10 D) Boron-11

D) Boron-11

An unknown compound with a molar mass of 155.06 g/mol consists of 46.47% C, 7.80% H, and 45.72% Cl. Find the molecular formula for the compound. A) CHCl B) C9H18Cl3 C) C6H12Cl D) C6H12Cl2 E) C3H6Cl

D) C6H12Cl2 46.47% /12 C, 7.80%H/1.008 , and 45.72% Cl/35.45. the find the molar mass then times C3H6Cl by 2=C6H12Cl2

section 2.6 What are the two different ions present in the compound CaS ? A) Ca+, S- B) Ca2-, S2+ C) Ca-, S+ D) Ca2+, S2- E) Ca, S

D) Ca2+, S2-

What are the two different ions present in the compound FeCl3? A) Fe2+, Cl3 - B) Fe3+, Cl3- C) Fe+, Cl- D) Fe3+, Cl- E) Fe+, Cl-

D) Fe3+, Cl-

What is the formula for the ionic compound containing iron (III) ions and iodide ions? A) FeI B) Fe2I C) FeI2 D) FeI3 E) Fe3I

D) FeI3

The formula for magnesium sulfate is A) MnS B) MgS C) MnSO3 D) MgSO4 E) MgSO3

D) MgSO4

The formula for sodium sulfide is A) NaS. B) K2S. C) NaS2. D) Na2S. E) SeS.

D) Na2S

What is the formula for the ionic compound containing sodium ions and nitride ions? A) NaN B) Na2N C) NNa2 D) Na3N E) NNa3

D) Na3N

An atom of bromine has a mass about four times greater than that of an atom of neon. Which choice makes the correct comparison of the relative numbers of bromine and neon atoms in 1,000 g of each element A) The number of bromine and neon atoms is the same. B) There are one thousand times as many bromine atoms as neon atoms. C) There are one thousand times as many neon atoms as bromine atoms. D) There are four times as many neon atoms as bromine atoms. E) There are four times as many bromine atoms as neon atoms

D) There are four times as many neon atoms as bromine atoms

The empirical formula of a compound of uranium and fluorine that is composed of 67.6% uranium and 32.4% fluorine is A) U2F B) U3F4 C) UF4 D) UF6 E) UF8

D) UF6

section2.4 The elements in a column of the periodic table are known as A) metalloids. B) a period. C) noble gases. D) a group. E) nonmetals.

D) a group

Atoms of the same element with different mass numbers are called A) ions. B) neutrons. C) allotropes. D) chemical families. E) isotopes

E) isotopes

Calculate the number of moles of xenon in 12.0 g of xenon. A) 1.00 mol D) 7.62 × 10-3 mol B) 0.0457 mol E) 0.0914 mol C) 0.183 mol

E) 0.0914 mol same concept

How many O atoms are in 4.39 g of CO2? A) 5.29 x 1024 O atoms D) 6.01 x 1022 O atoms B) 1.03 x 1022 O atoms E) 1.20 x 1023 O atoms C) 1.65 x 1023 O atoms

E) 1.20 x 1023 O atoms 4.39/44 x2 x6.022x10^23

What is the volume, in cubic centimeters, of a brick that is 4.0 in × 2.7 in × 8.0 in? A) 5.3 cm3 B) 53 cm3 C) 87 cm3 D) 4.8 × 102 cm3 E) 1.4 × 103 cm3

E) 1.4 × 103 cm3

Section: 3.3 How many F atoms are in 5.54 g of F2? A) 6.02 × 1023 atoms D) 8.78 × 1022 atoms B) 0.146 atoms E) 1.76 × 1023 atoms C) 0.292 atoms

E) 1.76 × 1023 atoms 5.54 g / 38.0 g/mol F2 = 0.1458 mol 2 mol F atoms per 1 mol F2 0.1458 mol x 2 x 6.022x10^23 = 1.76x10^23 Fluorine atom

1 US barrel = 4.21 cubic feet. Express this volume in liters. A) 3.99 × 10-5 L B) 1.99 × 10-2 L C) 19.9 L D) 105 L E) 119 L

E) 119 L

Calculate the molar mass of (NH4)2SO4 A) 114.11 g/mol D) 63.09 g/mol B) 228.22 g/mol E) 132.15 g/mol C) 118.14 g/mol

E) 132.15 g/mol

What is the molecular mass of nicotine, C10H14N2? A) 27.03 amu D) 81.12 amu B) 148.22 amu E) 162.23 amu C) 149.13 amu

E) 162.23 amu

How many moles of H are in 4.56 moles of NH2NH2? A) 4.52 moles H D) 18.39 moles H B) 4.56 moles H E) 18.24 moles H C) 9.12 moles H

E) 18.24 moles H 4.56 x 4

A piece of metal with a mass of 611 g is placed into a graduated cylinder that contains 25.1 mL of water, raising the water level to 56.7 mL. What is the density of the metal? A) 2.70 g/cm3 B) 7.13 g/cm3 C) 8.96 g/cm3 D) 10.5 g/cm3 E) 19.3 g/cm3

E) 19.3 611/(56.7-25.1) = 611/31.6 = 19.3 g/cm^3

How many sulfur atoms are present in 25.6 g of Al2(S2O3)3? A) 0.393 B) 6.00 C) 3.95 × 1022 D) 7.90 × 1022 E) 2.37 × 1023

E) 2.37 × 1023 Molar mass of Al2(S2O3)3 = 390.32 Moles = mass/ molar mass Moles = 25.6 grams / 390.32 grams per mole Moles = 0.066 Number of atoms of sulfur in one mole of Al2(S2O3)3 = 6 x 6.022 x 10^23 Number of atoms of sulfur contained by 0.066 moles of Al2(S2O3)3 = 0.066 x 6 x 6.022 x 10^23 Number of atoms of sulfur in 0.066 moles of Al2(S2O3)3 = 2.37 x 10^23

98. Aluminum metal reacts with nitric acid to produce aluminum nitrate and hydrogen gas. Identify the balanced reaction that describes this process. A) Al + HNO3 ® AlNO3 + H2 D) Al + 3HNO3 ® Al(NO3)3 + H2 B) Al + HNO3 ® AlNO3 + H E) 2Al + 6HNO3 ® 2Al(NO3)3 + 3H2 C) Al + 2HNO3 ® Al(NO3)2 + H2

E) 2Al + 6HNO3 ® 2Al(NO3)3 + 3H2

Calculate the mass of 4.50 moles of chlorine gas, Cl2. A) 6.34 × 10-2 g B) 4.50 g C) 15.7 g D) 160. g E) 319 g

E) 319 g • Find molar mass of Cl2 70.9060 • Times that by 4.50 moles

How many moles of O atoms are in 25.7 g of CaSO4? A) 0.189 mol D) 1.14 × 1023 mol B) 0.755 mol E) 4.55 × 1023 mol C) 4.00 mol

E) 4.55 × 1023 mo same concept

Give the correct number of significant figures to the problem below. 4.5 x 1014 / 8.3 x 108 = A) 5.4 x 1021 B) 5.4 x 1022 C) 5.4 x 106 D) 5.4 x 1014 E) 5.4 x 105

E) 5.4 x 105 if u do the prob u can see

Which of the following NH3 samples contains the greatest number of moles of NH3? A) 0.356 moles NH3 D) 8.90g NH3 B) 4.65 x 1023 NH3 molecules E) 6.78 x 101g NH3 C) 6.78 x 1022 NH3 molecules

E) 6.78 x 101g NH3

Formaldehyde has the formula CH2O. How many molecules are there in 0.11 g of formaldehyde? A) 6.1 × 10-27 B) 3.7 × 10-3 C) 4.0 D) 2.2 × 1021 E) 6.6 × 1022

D) 2.2 × 10^21

What is the theoretical yield of vanadium, in moles, that can be produced by the reaction of 2.0 moles of V2O5 with 6.0 moles of calcium based on the chemical reaction below? V2O5(s) + 5Ca(l) = 2V(l) + 5CaO(s) A) 1.0 mol B) 1.6 mol C) 2.0 mol D) 2.4 mol E) 4.0 mol

D) 2.4 mol SEE NOTES

How many C atoms are in 5.50 g of C? C? A) 5.01 x 1022 C atoms D) 2.76 x 1023 C atoms B) 3.31 x 1024 C atoms E) 5.50 x 1023 C atoms C) 6.02 x 1023 C atoms

D) 2.76 x 1023 C atoms same concept 550/126.022 x10^23

How many significant figures does the result of the following operation contain? 8.52010 × 7.90 A) 2 B) 3 C) 4 D) 5 E) 6

b) 3 same concept

What is the volume of a 2.5 g block of metal if its density is 4.75 g/cm3? A) 0.53 cm3 B) 1.9 cm3 C) 2.5 cm3 D) 4.75 cm3 E) 11.9 cm3

mass = 2.5g D = 4.75 g/cm^3 4.75 g/cm^3 = 2.5g / V To solve for V, multiply by V on both sides and then divide by 4.75 You get V = 2.5 g / 4.75 g/cm^3 V = .526 cm^3

see rest of section 2.3

see notes

see notes for rest of 2,7

see notes for rest of 2,7

Sulfur dioxide gas reacts with oxygen gas and water according to the chemical reaction below. When 4.5 g of SO2 are mixed with excess O2 and H2O, how many grams of H2SO4 are produced? 2SO2(g) + O2(g) + 2H2O(l) ® 2H2SO4(l)

2SO2 + O2 + 2H2O → 2H2SO4 1mol SO2 will produce 1 mol H2SO4 Molar mass SO2 = 64g/mol mol SO2 in 4.5g = 4.5/64 = 0.0703 mol You will produce 0.0703 mol H2SO4 Molar mass H2SO4 = 98g/mol Mass of 0.0703 mol H2SO4 = 0.0703*98 = 6.89g H2SO4 produced 4.5 x 1/64 x 98=6.89

Section: 1.8 The number 1.050 × 109 has how many significant figures? A) 2 B) 3 C) 4 D) 9 E) 13

3 1.050 x10^9=1050000000

Which one of the following is an example of a balanced chemical reaction? A) C3H6O + 4O2 ® 3CO2 + 3H2O D) 2C3H6O + 9O2 ® 6CO2 + 3H2O B) 2C3H6O + 9O2 ® 6CO2 + 6H2O E) C3H6O + 9O2 ® 3CO2 + 3H2O C) C3H6O + 3O2 ® 3CO2 + 3H2O

A) C3H6O + 4O2 ® 3CO2 + 3H2O D) 2C3H6O + 9O2

section 3.6 A compound with an empirical formula of C2H4Br has a molar mass of 215.90 g/mol. What is the molecular formula? A) C4H8Br2 B) C2H4Br C) CHBr D) C6H12Br3 E) C4H8Br

A) C4H8Br2 which is half the molar mass so the molecular formula is C4H8Br2 ..dibromobutane the molar mass is 107.9572 so 215.90/107.9572=2 multiply the c2h4 by 2 = c4h8br2

What is the empirical formula for C6H14O? A) C6H14O B) C3H7O C) C2H7O D) C12H28O2 E) CHO

A) C6H14O

What is the formula for the ionic compound containing calcium ions and oxide ions? A) CaO B) Ca2O C) CaO2 D) Ca3O E) CaO3

A) CaO

Iron metal reacts with hydrochloric acid to produce iron (II) chloride and hydrogen gas. Identify the balanced reaction that describes this process. A) Fe + 2 HCl ® FeCl2 + H2 D) 2Fe + 2HCl ® 2FeCl2 + H2 B) Fe + HCl ® FeCl2 + H2 E) Fe + 3HCl ® FeCl3 + H2 C) Fe + HCl ® FeCl + H Ans: A Category: Medium

A) Fe + 2 HCl ® FeCl2 + H2

What are the two different ions present in the compound Li3N? A) Li+, N3- B) Li3 +, N- C) Li3 3+, N3- D) Li+, N- E) Li3+, N3-

A) Li+, N3-

Ammonia reacts with oxygen to form nitric oxide and water vapor: 4NH3 + 5O2 = 4NO + 6H2O When 20.0 g NH3 and 50.0 g O2 are allowed to react, which is the limiting reagent? A) NH3 B) O2 C) NO D) H2O E) No reagent is limiting.

A) NH3

When 22.0 g NaCl and 21.0 g H2SO4 are mixed and react according to the equation below, which is the limiting reagent? 2NaCl + H2SO4 ® Na2SO4 + 2HCl A) NaCl B) H2SO4 C) Na2SO4 D) HCl E) No reagent is limiting.

A) NaCl

section 2.5 An anion is defined as A) a charged atom or group of atoms with a net negative charge. B) a stable atom. C) a group of stable atoms. D) an atom or group of atoms with a net positive charge

A) a charged atom or group of atoms with a net negative charge

The name for NH4NO3 is A) ammonium nitrate. D) hydrogen nitrogen oxide. B) ammonium nitrogen trioxide. E) hydrogen nitrate. C) ammonia nitrogen oxide.

A) ammonium nitrate.

Which one of the following elements is most likely to form a 2+ ion? A) calcium B) carbon C) fluorine D) oxygen E) sodium

A) calcium

Rutherford's experiment with alpha particle scattering by gold foil established that A) protons are not evenly distributed throughout an atom. B) electrons have a negative charge. C) electrons have a positive charge. D) atoms are made of protons, neutrons, and electrons. E) protons are 1840 times heavier than electrons.

A) protons are not evenly distributed throughout an atom.

Which of the following elements is chemically similar to oxygen? A) sulfur B) calcium C) iron D) nickel E) sodium

A) sulfur

How many significant figures does the difference 218.7201 - 218.63 contain? A) 1 B) 2 C) 3 D) 5 E) 7

A)1 218.7201 - 218.63 =1

An atom of bromine has a mass about four times greater than that of an atom of neon. How many grams of neon will contain the same number of atoms as 1,000 g of bromine? A) 4 g Ne B) 250 g Ne C) 400 g Ne D) 1,000 g Ne E) 4,000 g Ne

B) 250 g

What is the mass of 3.00 moles of ethanol, C2H6O? A) 4.99 × 10-24 g B) 138 g C) 6.52 × 10-2 g D) 50.0 g E) 1.81 × 1024

B ) 138 g 46 x 3

What is the mass of 8.25 × 1019 UF6 molecules? A) 352 g B) 0.0482 g C) 1.37 × 10-4 g D) 2.90 × 1022 g E) 8.25 × 1019 g

B) 0.0482 g 2) One mole UF6 contains 6.022*10^23 molecules. 3) The sample contains 8.25*10^19 molecules / 6.022*10^23 molecules/mol = 1.37*10^(-4) mol 4) 352 gUF6/mol * 1.37*10^(-4) mol = 0.0482 g UF6

An aluminum beverage can contain 12.0 fluid ounces of liquid. Express this volume in liters. (1 fl oz = 29.6 mL) A) 4.07 × 10-2 L B) 0.355 L C) 0.407 L D) 2.46 L E) 3.55 × 102 L

B) 0.355 L

How many grams of nitrogen are there in 7.5 g of Ca(NO3)2? A) 0.64 g B) 1.3 g C) 0.15 g D) 1.2 g E) 2.3 g

B) 1.3 g 7.5 grams Ca(NO3)2 (1 mole Ca(NO3)2/164.1 grams)(2 mole N/1 mole Ca(NO3)2)(6.022 X 10^23/1 mole N) = 5.5 X 10^22 atoms of nitrogen

What is the average mass, in grams, of one Rb atom A) 6.02 x 1023 g D) 85.47 g B) 1.42 x 10-22g E) 85.47 amu C) 5.15 x 1025 g

B) 1.42 x 10-22g 85.47/ 6.02 x 1023

118. What is the theoretical yield of vanadium, in moles, that can be produced by the reaction of 1.0 mole of V2O5 with 4.0 moles of calcium based on the following chemical reaction? V2O5(s) + 5Ca(l) ® 2V(l) + 5CaO(s) A) 1.0 mol B) 1.6 mol C) 2.0 mol D) 0.80 mol E) None of these

B) 1.6 mol SEE NOTES

In 1828, the diameter of the U.S. dime was changed to approximately 18 mm. What is this diameter when expressed in nanometers? A) 1.8 × 109 nm D) 1.8 × 10-5 nm B) 1.8 × 107 nm E) 1.8 × 10-10 nm C) 1.8 × 101 nm

B) 1.8 × 107 nm

How many moles of CF4 are there in 171 g of CF4? A) 0.51 mol B) 1.94 mol C) 4.07 mol D) 88.0 mol E) 171 mol

B) 1.94 mol 171/88

What is the theoretical yield of chromium that can be produced by the reaction of 40.0 g of Cr2O3 with 8.00 g of aluminum according to the chemical equation below? 2Al + Cr2O3 = Al2O3 + 2Cr A) 7.7 g B) 15.4 g C) 27.3 g D) 30.8 g E) 49.9 g

B) 15.4 g limite reagent is Al First, find the atomic weights from the periodic table. Cr = 51.9961 Al = 26.981539 O = 15.9994 Then calculate the molecular weight of Cr2O3 = 151.9904 Find the limiting reagent by converting grams of each reactant to moles. 8.00 g Al / 26.981539 = 0.2965 mol Al 40.0 g Cr2O3 / 151.9904 = 0.2632 mol Cr2O3 The limiting reagent is Al, because twice as much Al is needed as Cr2O3. From the balanced chemical equation, the moles of aluminum used equals the moles of chromium produced. Now calculate the grams of chromium produced. 0.2965 mol Cr * (51.9961) = 15.42 g Cr The answer is (B) 15.4 g Edit: The answer below is incorrect because aluminum is the limiting reagent; that is, the aluminum is all used up before all the Cr2O3 can be used. Thus, you cannot calculate the Cr produced by assuming all the Cr in Cr2O3 is converted to Cr.

Balance the following and list the coefficients in order from left to right. ___ Cr + ___ H2SO4 = ___ Cr2(SO4)3 + ___ H2 A) 2, 3, 1, 2 B) 2, 3, 1, 3 C) 1, 3, 1, 3 D) 4, 6, 2, 6 E) 1, 3, 1, 2

B) 2, 3, 1, 3 2 Cr + 3 H2SO4 = Cr2(SO4)3 + 3 H2

Which of the following samples contains the greatest number of atoms? A) 100 g of Pb D) 5 g of He B) 2.0 mole of Ar E) 20 million O2 molecules C) 0.1 mole of Fe

B) 2.0 mole of Ar

Suppose a house has a floor area of 2,250 square feet. What is this area in units of square centimeters? A) 2.42 cm2 D) 6.86 × 104 cm2 B) 2.09 × 106 cm2 E) 101 cm2 C) 5.02 × 104 cm2

B) 2.09 × 106 cm2

How many sulfur atoms are there in 21.0 g of Al2S3? A) 8.42 × 1022 atoms D) 6.02 × 1023 atoms B) 2.53 × 1023 atoms E) 6.30 × 1026 atoms C) 2.14 × 1023 atoms

B) 2.53 × 1023 atoms Use avagrado # 21.0/150.1581]mas x 3 x 6.022 x10^23

What is the coefficient for O2 when the following combustion reaction of a hydrocarbon is balanced? ___ C7H14 + ___ O2 = ___ CO2 + ___ H2O A) 42 B) 21 C) 11 D) 10 E) none of these

B) 21 ___ C7H14 + ___ O2 = ___ CO2 + ___ H2O 2 C7H14 + 21 O2 = 14 CO2 + 14 H2O

Vanadium(V) oxide reacts with calcium according to the chemical equation below. When 10.0 moles of V2O5 are mixed with 10.0 moles of Ca, which is the limiting reagent? V2O5(s) + 5Ca(l) ® 2V(l) + 5CaO(s) A) V2O5 B) Ca C) V D) CaO E) No reagent is limiting.

B) Ca

The formula for calcium phosphate is A) CaPO4. B) Ca3(PO4)2. C) Ca2(PO4)3. D) Ca3P2. E) Ca3(PO3)2.

B) Ca3(PO4)2.

Ammonia reacts with oxygen to form nitric oxide and water vapor: 4NH3 + 5O2 = 4NO + 6H2O When 40.0 g NH3 and 50.0 g O2 are allowed to react, which is the limiting reagent? A) NH3 B) O2 C) NO D) H2O E) No reagent is limiting

B) O2 SEE NOTES With all due respect, PWD and "the one" have no idea how to deal with limiting reactant problems. The actual masses can't be compared to determine the limiting reactant. That must come from the moles of each reactant and the balanced chemical equation. 40 g NH3 is 2.35 mol 50 g O2 is 1.56 mol According to the balanced equation 4 mol of NH3 reacts with 5 mol O2. Therefore 2.35 mol NH3 will react with (5/4*2.35) moles of O2, which is 2.93 moles of O2. Since you only have 1.56 moles of O2, then O2 is the limiting reactant.

The scientist who determined the magnitude of the electric charge of the electron was A) John Dalton. D) Henry Moseley. B) Robert Millikan. E) R. Chang. C) J. J. Thomson

B) Robert Millikan

Which of the following elements is chemically similar to magnesium? A) sulfur B) calcium C) iron D) nickel E) potassium

B) calcium

Chapter 2 section 2.2 1. In a cathode ray tube A) electrons pass from the anode to the cathode. B) electrons pass from the cathode to the anode. C) protons pass from the anode to the cathode. D) protons pass from the cathode to the anode.

B) electrons pass from the cathode to the anode.

When J. J. Thomson discovered the electron, what physical property of the electron did he measure? A) its charge, e D) its mass, m B) its charge-to-mass ratio, e/m E) its atomic number, Z C) its temperature, T

B) its charge-to-mass ratio, e/m

Which one of the following elements is most likely to form a 2- ion? A) scandium B) selenium C) silicon D) strontium E) iodine

B) selenium

How many milliliters is 0.005 L? A) 0.5 mL B) 5 mL C) 0.50 mL D) 0.000005 mL E) 200 mL Ans: B Category: Medium Section: 1.9

B)5 0.005 x 1000

Convert 5.00 x 102 milliliters to quarts. (1L = 1.06 qt) A) 1.88 qt B) 0.472 qt C) 0.528 qt D) 4.72 × 105 qt E) 5.28 × 105 qt

C) 0.528

How many molecules are there in 8.0 g of ozone, O3? A) 3.0 molecules D) 3.0 × 1023 molecules B) 3.6 × 1024 molecules E) 6.0 × 1023 molecules C) 1.0 × 1023 molecules

C) 1.0 × 10^23 molecules 8.0/47.99 x 6.022 x10^23= 1.00

How many sodium atoms are there in 6.0 g of Na3N? A) 3.6 × 1024 atoms D) 0.22 atoms B) 4.6 × 1022 atoms E) 0.072 atoms C) 1.3 × 1023 atoms

C) 1.3 × 1023 atoms Molecular weight for Na3N = 83 g/mol 6.0g / 83g/mol = 0.0723 mol Na3N 0.0723 mol Na3N * 3mol Na/1mol Na3N = 0.217 mol Na 0.217 mol * 6.022*10^23 atoms/mol = 1.306*10^23 sodium atoms in 6 grams of Na3N

How many carbon atoms are there in 15 lbs of sugar, C12H22O11? A) 4.1 x 1028 C atoms D) 2.6 x 1022 C atoms B) 1.2 x 1026 C atoms E) 3.2 x 1023 C atoms C) 1.4 x 1026 C atoms

C) 1.4 x 1026 C atoms Convert 10 lbs to grams, divide by the molecular weight of sugar, multiply by avogadro's number, multiply by 12. there is the answer. sugar is = C12 H22 O11 the molecular weight or molar mass is 342 g/mols. the Avogadro's number is, 6.022 X 10^23. 1 pound is = 453.59 g 453.59 g * 10 pounds

Ammonia reacts with oxygen to form nitric oxide and water vapor: 4NH3 + 5O2 ® 4NO + 6H2O What is the theoretical yield of water, in moles, when 40.0 g NH3 and 50.0 g O2 are mixed and allowed to react? A) 1.30 mol B) 1.57 mol C) 1.87 mol D) 3.53 mol E) None of these

C) 1.87 mol O2 IS LIMITED 50/31.99 =1.56X6H20/5O2=1.87

A magnesium ion, Mg2+, has A) 12 protons and 13 electrons. D) 24 protons and 22 electrons. B) 24 protons and 26 electrons. E) 12 protons and 14 electrons. C) 12 protons and 10 electrons.

C) 12 protons and 10 electrons

How many grams of Cl2 can be prepared from the reaction of 16.0 g of MnO2 and 30.0 g of HCl according to the following chemical equation? MnO2 + 4HCl ® MnCl2 + Cl2 + 2H2O A) 0.82 g B) 5.8 g C) 13.0 g D) 14.6 g E) 58.4 g

C) 13.0 g Moles of MnO2 in 16g = mass/mr= 16 / 77 = 0.21 1:1 ratio of MnO2 to Cl2 Moles of Cl2 = 0.21 Mr of Cl2 = 71 Mass = moles x Mr = 0.21 x 71 = 14.8g. Answer = 14.8g

A) 79.90 amu B) 79.90 g C) 159.8 amu D) 159.8 g E) 2.65 x 10-22 amu

C) 159.8 amu

What is the theoretical yield of vanadium that can be produced by the reaction of 40.0 g of V2O5 with 40.0 g of calcium based on the following chemical reaction? V2O5(s) + 5Ca(l) = 2V(l) + 5CaO(s) A) 5.6 g B) 11.2 C) 20.3 g D) 22.4 g E) 40.0 g

C) 20.3 g

How many significant figures does the result of the following sum contain? 8.520 + 2.7 A) 1 B) 2 C) 3 D) 4 E) 5 Ans: C Category: Easy Section: 1.8

C) 3 same concept

What is the coefficient of O2 when the following equation is properly balanced? ___ CH3OH + ___ O2 = ___ CO2 + ___ H2O A) 1 B) 2 C) 3 D) 7 E) none of these

C) 3 CH3OH + ___ O2 = ___ CO2 + ___ H2O 2 CH3OH + 3 O2 = 2 CO2 + 4 H2O

When balanced the coefficient of O2 in the following equation is __ C2H4 + __ O2 ® __ CO2 + __ H2O A) 1. B) 2. C) 3. D) 4. E) 6.

C) 3. _ C2H4 + __ O2 = __ CO2 + __ H2O C2H4 + 3 O2 = 2 CO2 + 2 H2O

Calculate the mass of 3.00 moles of CF2Cl2. A) 3.00 g B) 174 g C) 363 g D) 1.81 × 1024 g E) 40.3 g

C) 363 g 3.00 moles of 120.9135 g/molCF2Cl2.

What is the mass of 4.50 x 1022 Cu atoms? A) 7.47 x 10-2 g B) 7.47 x 10-2 amu C) 4.75 g D) 63.55 amu E) 63.55

C) 4.75 g (4.50 x 10^22 Cu atoms) / (6.022 x 10^23 atoms/mol) x (63.5463 g Cu/mol) = 4.75 g

What is the theoretical yield of H2O that can be obtained from the reaction of 4.5 g H2 and excess O2? 2H2(g) + O2(g) = 2H2O(g) A) 4.5 g B) 9.0 g C) 40. g D) 80. g E) 81 g

C) 40 4.5/2.015h2 x 1x18.01h20=40

What is the mass of 0.55 mole of C6H6? A) 78.11 g B) 78.11 amu C) 42.96 g D) 42.96 amu E) 7.04 x 10-3 g Ans: D Category: Easy Section: 3.3

C) 42.96 g 78.x 0.55

section 3.4 A mass spectrometer works by ionizing atoms or molecules, and then accelerating them through oppositely charged plates. The mass is obtained by A) measuring the force of impact on a detecting screen, and then calculating the mass using force = mass × acceleration. B) suspending the ions in an applied electric field, and then calculating mass by the setting the downward gravitational force equal to the upward electrostatic force. C) measuring the magnitude of deflection as the ions pass through a magnetic field to obtain the charge-to-mass ratio, and then calculating the mass from that ratio. D) measuring the time it takes for the ions to hit the detector at a known distance to calculate the acceleration, and then calculating mass from force = mass × acceleration.

C) measuring the magnitude of deflection as the ions pass through a magnetic field to obtain the charge-to-mass ratio, and then calculating the mass from that ratio

How many significant figures are there in 0.3070 g? A) 6 B) 5 C) 4 D) 3 E) 2

C)4

What is the formula for the ionic compound containing calcium ions and nitrate ions? A) Ca3N2 B) Ca(NO3)2 C) Ca2NO3 D) Ca2NO2 E) CaNO3

Ca(NO3)2

Calculate the mass of C in 5.46 g of C2H4? A) 0.455 g C B) 4.68 g C C) 65.6 g C D) 13.1 g C E) 24.0 g C

Calculate the molar mass of Cl2o7 • Divide by 5.46 / C2H428 • Times by C2 24 by the molar mass

Convert 2.340 x 10-4 to decimal format. A) 23,400 B) 2,340 C) 0.000234 D) 0.0002340 E) 0.002340

D) 0.0002340

Balance the following equation and list the coefficients in order from left to right. __ SF4 + __ H2O ® __ H2SO3 + __ HF A) 1, 1, 1, 4 B) 2, 6, 2, 8 C) 1, 2, 1, 4 D) 1, 3, 1, 4 E) 2, 3, 2, 8

D) 1, 3, 1, 4 SF4 + 3 H2O = H2SO3 + 4 HF

What is the average mass, in grams, of one Zn atom? A) 65.39 amu D) 1.09 x 10-22 g B) 65.39 g E) 1.661 x 10-24g C) 3.94 x 1025g

D) 1.09 x 10-22 g • 65.39/6.022 x 10^23

The "escape velocity" from Earth (the speed required to escape Earth's gravity) is 2.5 × 104 miles per hour. What is this speed in m/s? (1 mile = 1609 m) A) 4.2 × 10-3 m/s D) 1.1 × 104 m/s B) 6.9 m/s E) 4.0 × 107 m/s C) 4.2 × 102 m/s

D) 1.1 × 104 m/s

Iridium is essentially tied with osmium for the distinction of being called the "densest element" with a density of 22.5 g/cm3. What would be the mass in pounds of a 1.0 ft × 1.0 ft × 1.0 ft cube of iridium. (1 lb = 453.6 g) A) 1.5 lb B) 5.2 lb C) 6.20 lb D) 1.4 × 103 lb E) 6.4 × 105 lb

D) 1.4 × 103 lb

How many moles of Cl atoms are there in 65.2 g CHCl3? A) 0.548 mol B) 1.09 mol C) 3.30 × 1023 mol D) 1.64 mol E) 3.00 mol

D) 1.64 mol divide 65.2g by the molar mass of the compound (119g). then multiply by 3 because there are 3 moles of Cl per compound

How many fluorine atoms are there in 65 g of CF4? A) 0.74 atoms D) 1.8 × 1024 atoms B) 3.0 atoms E) 2.4 × 1023 atoms C) 4.5 × 10

D) 1.8 × 1024 atoms How many fluorine atoms are there in 65 g of CF4? convert grams of CF4 to moles of CF4, multiply by Avagadro's number to convert to # of CF4 molecules, multiple by 4 (because of 4 F atoms per molecule) to get # of F atoms. mol wt (CF4) = 1 88.01 g/mol 65 g / 88.01 g/mol = 0.74 mol CF4 0.74 mol x 6.022 x 1023 molecules/mol = 4.5 x 1023 molecules of CF4 (4.5 x 1023 molecules) x 4 F-atoms/molecule = 1.8 x 1024 F atoms

Aluminum hydroxide reacts with nitric acid to form aluminum nitrate and water. What mass of water can be formed by the reaction of 15.0 g of aluminum hydroxide with excess nitric acid? A) 1.15 g B) 3.46 g C) 6.14 g D) 10.4 g E) 45.0 g

D) 10.4 g Al(OH)3(s) + 3HNO3(aq) --> Al(NO3)3(aq) + 3HOH(l) 15.0 g ............... .............. ............. .......... ??? g 15.0 g Al(OH)3 x (1 mo Al(OH)3 / 78.0g Al(OH)3) x (3 mol HOH / 1 mol Al(OH)3) x (18.0g HOH / 1 mol HOH) = 10.4 g HOH

Calculate the average atomic mass of silver using the following data: Isotope Abundance Mass 107Ag 51.84% 106.9051amu 109Ag 48.16% 108.9048amu A) 106.91 amu D) 107.87 amu B) 108.00 amu E) 108.90 amu C) 107.90 amu

D) 107.87 amu 107Ag .5184 x 106.9051amu + 109Ag .4816x 108.9048amu

What is the coefficient of H2O when the following equation is properly balanced? ___ Al4C3 + ___ H2O -> ___ Al(OH)3 + ___ CH4 A) 3 B) 4 C) 6 D) 12 E) 24

D) 12 What is the coefficient of H2O when the following equation is properly balanced? Al4C3 + 12 H2O = 4 Al(OH)3 + 3 CH4

If a car has an EPA mileage rating of 30 miles per gallon, what is this rating in kilometers per liter? (1 L = 1.06 qt) A) 200 km/L B) 180 km/L C) 70 km/L D) 13 km/L E) 11 km/L

D) 13 km/L

An aluminum ion, Al3+, has: A) 13 protons and 13 electrons D) 13 protons and 10 electrons B) 27 protons and 24 electrons E) 10 protons and 13 electrons C) 16 protons and 13 electrons

D) 13 protons and 10

Calculate the mass of FeS formed when 9.42 g of iron reacts with 8.50 g of sulfur according to the following reaction. Fe(s) + S(s) = FeS(s) A) 17.9 g B) 87.9 g C) 26.0 g D) 14.8 g E) 1.91 × 10-3 g

D) 14.8 g see que 111

1 barrel of oil contains 42.0 gallons. How many liters is this? (1L = 1.06 qt)

D) 158 L

A block of iron has a mass of 826 g. What is the mass of a block of magnesium that has the same volume as the block of iron? The following densities at 25°C are provided: magnesium, 1.7 g/cm3 ; graphite, 1.8 g/cm3 ; iron, 7.9 g/cm3. A) 1,400 g B) 3,800 g C) 830 g D) 180 g E) none of them are within 10 g of the right answer

D) 180 g

Which of the following represents the largest mass? A) 2.0 × 102 mg D) 2.0 × 102 cg B) 0.0010 kg E) 10.0 dg C) 1.0 × 105 ng

D) 2.0 × 102 cg

Using the arithmetic problem below, determine the correct number of significant figures. (1.5 × 10-4 × 61.3) + 2.01 = A) 2.0192 B) 2.0 C) 2.019 D) 2.02 E) 2.019195

D) 2.02 has to be 3 sig fig

Calculate the mass of N in 2.34 g of N2H4? A) 4.68 g N B) 65.6 g N C) 28.02 g N D) 2.05 g N E) 2.34 g N

D) 2.05 g N

Give the correct number of significant figures to the problem below. 6.2 x 10-13 x 5.68 x 108 = A) 3.5 x 10-13 B) 3.5 x 10-5 C) 3.5 x 10-104 D) 3.5 x 10-4 E) 3.5 x 10-21

D) 3.5 x 10-4 same concept

The reaction of 60.0 g of aluminum oxide with 30.0 g of carbon produced 22.5 g of aluminum. What is the percent yield for this reaction? Al2O3 + 3C = 2Al + 3CO A) 25.0 % B) 31.8 % C) 44.9 % D) 50.1 % E) 70.9 %

E) 70.9 % Al2O3(s) + 3C(s) --> 2Al(s) + 3CO(g) 60.0g ........30.0g .......?g This is a limiting reactant problem. Use each reactant to compute the mass of Al. The smaller of the two will be the theoretical yield, and the reactant which gives the smaller amount of product will be the limiting reactant. 60g Al2O3 x (1 mol Al2O3 / 102.0g Al2O3) x (2 mol Al / 1 mol Al2O3) x (27.0g Al / 1 mol Al) = 31.8g Al 30.0g C x (1 mol C / 12.0g C) x (2 mol Al / 3 mol C) x (27.0g Al / 1 mol Al) = 45.0g Al The theoretical yield is 31.8g of Al. Percent yield = 22.5 / 31.8 x 100 = 70.8%

Which one of the following is an example of a balanced chemical reaction? A) HCl + KMnO4 ® Cl2 + MnO2 + H2O + KCl B) HCl + KMnO4 ® Cl2 + MnO2 + 2H2O + KCl C) 2HCl + 2KMnO4 ® Cl2 + MnO2 + 2H2O + 2KCl D) 6HCl + 2KMnO4 ® 2Cl2 + 2MnO2 + 4H2O + 2KCl E) 8HCl + 2KMnO4 ® 3Cl2 + 2MnO2 + 4H2O + 2KCl

E) 8HCl + 2KMnO4 ® 3Cl2 + 2MnO2 + 4H2O + 2KCl

The percent composition by mass of a compound is 76.0% C, 12.8% H, and 11.2% O. The molar mass of this compound is 284.5 g/mol. What is the molecular formula of the compound

E) C18H36O2

compound with an empirical formula of C2H3Br2 has a molar mass of 373.69 g/mol. What is the molecular formula? A) C2H3Br2 B) CHBr C) C6H9Br6 D) C4H6Br2 E) C4H6Br4

E) C4H6Br4 multiply everthing by 2

Which of the following scientists developed the nuclear model of the atom? A) John Dalton D) Henry Moseley B) Robert Millikan E) Ernest Rutherford C) J. J. Thomson

E) Ernest Rutherford

Which of the following elements is most likely to be a good conductor of electricity? A) N B) S C) He D) Cl E) Fe

E) Fe

Which of the following is the formula for hydroiodic acid? A) HIO4 B) HIO3 C) HIO2 D) HIO E) HI

E) HI

One mole of iron A) is heavier than one mole of lead (Pb). D) weighs the same as one mole of lead. B) is 77.0 g of iron. E) None of the above. C) is 26.0 g of iron.

E) None of the above

The molecular formula of aspirin is C9H8O4. How many aspirin molecules are present in one 500-milligram tablet? A) 2.77 molecules D) 1.67 × 1021 molecules B) 2.77 × 10-3 molecules E) None of these is correct. C) 1.67 × 1024 molecules

E) None of these is correct

The element oxygen consists of three naturally occurring isotopes: 16O, 17O, and 18O. The atomic mass of oxygen is 16.0 amu. What can be implied about the relative abundances of these isotopes? A) More than 50% of all O atoms are 17O. B) Almost all O atoms are 18O. C) Almost all O atoms are 17O. D) The isotopes all have the same abundance, i.e. 33.3%. E) The abundances of 17O and 18O are very small.

E) The abundances of 17O and 18O are very small.

chapter 3 1. An atom of helium has a mass about four times greater than that of an atom of hydrogen. Which choice makes the correct comparison of the relative numbers of helium and hydrogen atoms in equal masses of the two elements? A) There are about four times as many helium atoms as hydrogen atoms. B) There are about two times as many helium atoms as hydrogen atoms. C) The number of helium and hydrogen atoms is the same. D) There are about half as many helium atoms as hydrogen atoms. E) There are about one-fourth as many helium atoms as hydrogen atoms

E) There are about one-fourth as many helium atoms as hydrogen atoms

The name for Ba(OH)2 is A) barium hydrogen oxide. D) beryllium hydroxide. B) boron hydroxide. E) barium hydroxide. C) barium hydrate.

E) barium hydroxide.

Which of the following elements is chemically similar to potassium? A) calcium B) arsenic C) phosphorus D) cerium E) cesium

E) cesium

What are the ions present in the compound CO2? A) C4+, 2 O2- B) C2+, 2 O- C) C2+, O2- D) C2+, O2 2- E) no ions present

E) no ions

What are the ions present in the compound CH4? A) C4+, H+ B) C4-, H+ C) C-, H+ D) C4- H4+ E) no ions present

E) no ions present

What is the ion ClO4 - named? A) chloride ion D) perchlorite ion B) chlorite ion E) perchlorate ion C) hypochlorite ion

E) perchlorate ion

How many moles of HCl are represented by 1.0 × 1019 HCl molecules? A) 1.7 × 10-5 mol D) 37 mol B) 1.5 × 10-3 mol E) 6.0 × 104 mol C) 1.0 × 1019 mol

Here you can already see you have less than one mole of molecules. A) 1.7 × 10-5 mol 1.0 x 10^19 divided by 6.0221415 x 10^23 = 1.661 x 10^-5

After carrying out the following operations, how many significant figures are appropriate to show in the result? (13.7 + 0.027) ÷ 8.221 A) 1 B) 2 C) 3 D) 4 E) 5

the smallest number is the sig fig C) 3