CH 221 FALL 2010 –MIDTERM 11

CH 221 FALL 2010 - FIRST MIDTERM EXAM

Version 1

This exam has 22 questions worth 5 pts each, plus one question worth 2 pts.

The total possible scoreis 112 pts.

DO NOT OPEN THIS EXAM UNTIL TOLD TO DO SO

Before the exam begins you can do the following on the Scantron answer sheet. Use a #2 pencil.

1. Fill in your name (LAST NAME, FIRST NAME) in the large box on the left. Don't forget to bubble in the circles below your name.

2. Fill in your student ID number in the box labeled "IDENTIFICATION NUMBER". Do not use dashes or blank spaces. Fill in the circles as well.

3. In the box labelled "CLASS SECTION NUMBER", enter the appropriate number

8 am class = section 001 9 am class = section 002 10 am class = section 003

11am class = section 004 12pm class = section 005

4. In the lower right corner, in the box labelled "FORM NUMBER", write in the exam version number (1, 2, 3, 4 etc.) given above in the shaded box and fill in the bubble.

ONLY ONE APPROVED NOTECARD IS ALLOWED

ALL PHONES AND OTHER ELECTRONIC DEVICES OTHER THAN CALCULATORS MUST BE OFF

You may keep this exam packet and your notecard when the exam period is complete.

Hand in the Scantron answer sheet to a TA at the end of the exam.

Periodic Table
1.Which of the following is a chemical property?

A.The ductility (ease of deformation)of silver.

B.The ability of a hydrogen gas to fill a container of any size.

C.The ability of water to freeze, melt and boil.

D.The ability of oxygen to rust steel.

E.The ability of ZnO to produce a voltage if pressure is applied to it.

2.Which of the following statements is NOT TRUE?

A. Gas molecules are far less densely packed than liquid molecules.

B.Solids are typically less densely packed than liquids

C.Evaporation is the phenomenon of a substance going from liquid to vapor.

D.Even though solids are typically tightly packed, it is still possible to chemically react them.

E.Solid water is less dense than liquid water.

3.Express the answer to the following to the correct number of significant figures:

(2.54 × 10-3 mol × 738.3254 g/mol) + 4.3 g

A. 6.18 mol

B.6.176 g

C.6.2 g

D.6.18 g

E.6200 g

4.Convert the volume of a cube with edges of 10.0 ft into liters. 1 in = 2.54 cm; 1 ft = 12 in

A. 0.305 L

B.305 L

C.1.64 x 104 L

D.2.83 x 104 L

E.2.83 x 107 L

5. In medicine it is common to have dosages listed in milligrams of drug per kilogram of

bodyweight (mg/kg). An oral dosage of 60.0mg of codeine is common for a 180lb man. What is the dosage in mg/kg? [1.00 kg = 2.205 lbs]

A.0.151 mg/kg

B.0.735 mg/kg

C.4.91 x 103 mg/kg

D.2.38 x 104 mg/kg

E.1.51 mg/kg

6.Which of the following statements concerning early experiments and ideas about atomic structure turned out to be TRUE?

A. The atom consists of negative electrons floating in a background positive charge.

B. All carbon atoms are identical.

C. Most of the mass of an atom is concentrated in a small volume at the center.

D. The formation of a compound can result in the destruction of an atom.

E. Atoms consist solely of protons and electrons.

7. Which is the correct definition of mass number?

A. The number of particles in the nucleus

B. The number of protons in the nucleus

C. The number of neutrons in the nucleus

D. The number of protons plus neutrons in the nucleus

E. The mass of a nucleus

8. Choose the correct symbol for the isotope of Fe that has 30 neutrons.

A. 3026Fe

B.2630Fe

C. 5226Fe

D. 5630Fe

E. 5626Fe

9. Which of the following lists of elements is an element which tends to lose one electron when forming an ionic compound, a noble gas, an element which tends to gain one electron when forming an ionic compound, and a transition metal?

A.F, Ne, Li, Fe

B.Na, Ne, Cl, Cr

C.Ba, Kr, Br, Cr

D.Cs, N, Ar, Fe

E.F, He, Rb, Al

10.Chemium has two naturally occurring isotopes. 151Ch has a mass of 150.92 g/mol and is 18.82% abundant.153Ch has a mass of 152.97 g/mol and is 81.18% abundant. What is the average atomic mass of Chemium?

A.151.31 g/mol

B.152.97 g/mol

C.150.92 g/mol

D.151.95 g/mol

E.152.58 g/mol

11.Which of these statements is NOT CORRECT?

A. Avogadro’s number is the number of H atoms in 1.0079 g of H atoms.

B. The mass of 2 moles of Fe atoms is twice the mass of 1 mole of Fe atoms.

C.1 mole of O2 contains 6.02 × 1023 O atoms.

D. If the atomic mass of an element is x amu, then its molar mass is x g/mol.

E. 1 mole of H2O contains twice as many atoms of H as O.

12.How many Ca atoms are there in 2.04 g of Ca? [NA = 6.022 x 1023]

A. 4.92 × 1023 atoms

B 3.07 × 1022 atoms

C. 4.92 × 1025 atoms

D. 8.45 × 10-26 atoms

E. 40.08 atoms

13.Prazosin (trade names Minipress,Vasoflex,Pressin and Hypovase) is a sympatholytic drug used to treat high blood pressure (hypertension). It belongs to the class of alpha-adrenergic blockers, which lower blood pressure by relaxing blood vessels. There are 1.178 x 1024 Prazosin molecules in 750.0 g of Prazosin. What is the molar mass of Prazosin?

A.709.4 g/mol

B.318.7 g/mol

C.236.1 g/mol

D.383.4 g/mol

E.The answer cannot be calculated without the molecular formula of Prazosin.

14.The molar mass of calcium acetate Ca(CH3COO)2 is:

A.6.879 x 1025 g/mol

B.112.21 g/mol

C.158.17 g/mol

D.104.15 g/mol

E.99.13 g/mol

15.Methyl salicylate (a compound that smells like wintergreen) contains:

A.an alcohol functional group and a ketone functional group

B.an alcohol functional group and an ether functional group

C.an alcohol functional group and an ester functional group

D.an alcohol functional group and an amide functional group

E.an alcohol functional group and an aldehyde functional group

16.Upon combustion in excess oxygen, 0.4780 grams of a compound containing only carbon, hydrogen, and oxygen produces 0.6780 grams of CO2 (g) and 0.4165 grams of H2O (g). What is the empirical formula of the compound?

A.C4H8O

B.C2H4O

C.CH2O

D.CH3O

E.C2H3O2

17.What is the mass percent composition of sodium in sodium phosphate Na3PO4?

A.42.1 %

B.20.0 %

C.34.7 %

D.11.1 %

E.14.0%

18.When the reaction below is correctly balanced,

C11H24 (l) + O2 (g) → CO2 (g) + H2O (g)

A.17 O2 are consumed

B.11 O2 are consumed

C.22 O2 are consumed

D.12 O2 are consumed

E.34 O2 are consumed

19 .The name of Co3(PO4)2 is ______and the name of N2O4 is ______.

A.cobalt(III) phosphate, dinitrogen tetroxide

B.cobalt(II) phosphate, dinitrogen tetroxide

C.cobalt(III) phosphate, nitrogen oxide

D.cobalt(II) phosphate, nitrogen oxide

E.tricobalt diphosphate, dinitrogen tetroxide

20.Which of the following pairs of elements can combine to form an ionic compound?

A.Sodium and calcium

B.Carbon and oxygen

C.Calcium and sulfur

D.Carbon and nitrogen

E.Fluorine and neon

21.Aluminum metal dissolves in nitric acid to produce aluminum nitrate and hydrogen gas as follows:

2Al (s) + 6HNO3 (aq) → 2Al(NO3)3 (aq) + 3H2 (g)

If 3.00 moles of aluminum metal are dissolved completely in an excess of nitric acid, how many grams of hydrogen gas will be evolved by the reaction assuming a yield of 100%?

A. 4.03 g H2

B.4.54 g H2

C. 9.07 g H2

D.2.02 g H2

E.6.05 g H2

22.If 5.00 moles of iron metal are reacted with hydrochloric acid according to the following reaction:

2Fe (s) + 6HCl (aq) → 2FeCl3 (aq) + 3H2 (g)

and the reaction yields 760 g ofFeCl3, what is the percent yield of the reaction?

A. 55.5%

B. 234%

C. 46.9%

D.93.7%

E.97.2%

TWO POINT QUESTION

23. Can you pass this class without passing the lab portion?

A. Yes

B. No