1101-2nd Midterm Exam_12/15/21_(A)
1) A 5-ounce cup of raspberry yogurt contains 6.0 g of protein, 2.0 g of fat, and 20.2 g of carbohydrate. The fuel values for protein, fat, and carbohydrate are 17, 38, and 17 kJ/g, respectively. The fuel value of this cup of yogurt is __________ kJ.
A) 72 B) 630 C) 520 D) 340 E) 720
Answer: C
2) A sample of aluminum metal absorbs 8.32 J of heat, upon which the temperature of the sample increases from 23.2 °C to 30.5 °C. Since the specific heat capacity of aluminum is 0.90 J/g-K, the mass of the sample is __________ g.
A) 72 B) 1.3 C) 7.5 D) 7.3 E) 65
Answer: B
3) A __________ H corresponds to an __________ process.
A) positive, endothermic B) zero, endothermic C) negative, endothermic D) zero, exothermic
E) positive, exothermic Answer: A
4) The internal energy of a system __________.
A) refers only to the energies of the nuclei of the atoms of the component molecules B) is the sum of the kinetic energy of all of its components
C) is the sum of the rotational, vibrational, and translational energies of all of its components D) is the sum of the potential and kinetic energies of the components
E) none of the above Answer: D
5) For which one of the following reactions is the value of H°rxn equal to H°f for the product?
A) H2 (g) + 1/2 O2 (g) H2O (l)
B) 2 C (s, graphite) + 2 H2 (g) C2H4 (g) C) H2 (g) + O2 (g) H2O2 (l)
D) 1/2 N2 (g) + O2 (g) NO2 (g) E) all of the above
Answer: E
6) For the species in the reaction below, Hf° is zero for __________.
2Co (s) + H2 (g) + 8PF3 (g) 2HCo(PF3)4 (l) A) H2 (g)
B) PF3 (g) C) Co (s)
D) HCo(PF3)4 (l)
E) both Co(s) and H2 (g)
7) When a system __________, E is always negative.
A) gives off heat and does work B) absorbs heat and does work
C) gives off heat and has work done on it D) absorbs heat and has work done on it
E) none of the above is always negative.
Answer: A
8) The specific heat capacity of solid copper metal is 0.385 J/g-K. How many joules of heat are needed to raise the temperature of a 1.55-kg block of copper from 33.0 °C to 77.5 °C?
A) 1.79 × 105 B) 5.58 × 10-6 C) 26.6 D) 2.66 × 104 E) 0.00558
Answer: D
9) The specific heat capacity of methane gas is 2.20 J/g-K. How many joules of heat are needed to raise the temperature of 5.00 g of methane from 36.0 °C to 75.0 °C?
A) 429 B) 22.9 C) 0.0113 D) 1221 E) 88.6
Answer: A
10) Which one of the following is an incorrect orbital notation?
A) 4s B) 3py C) 3f D) 2s E) 4dxy
Answer: C
11) Which electron configuration represents a violation of the Pauli exclusion principle?
A)
B)
C)
D)
E)
12) Which one of the following configurations depicts an excited oxygen atom?
A) [He]2s22p4 B) 1s22s22p2 C) 1s22s22p1 D) 1s22s22p23s2
E) 1s22s22p4 Answer: D
13) Electromagnetic radiation with a wavelength of 531 nm appears as green light to the human eye. The energy of one photon of this light is 3.74 × 10-19 J. Thus, a laser that emits 1.3 × 10-2 J of energy in a pulse of light at this wavelength produces __________ photons in each pulse.
A) 9.2 × 10-24 B) 3.5 × 1016 C) 2.9 × 10-17 D) 6.5 × 1013 E) 1.8 × 1019 Answer: B
14) The ground state configuration of tungsten is __________.
A) [Xe]6s24f145d4 B) [Ne]3s1 C) [Ar]4s23d3 D) [Xe]6s24f7
E) [Kr]5s24d105p5 Answer: A
15) Which one of the following is the correct electron configuration for a ground-state nitrogen atom?
A)
B)
C)
D)
E) None of the above is correct.
Answer: C
16) Consider the general valence electron configuration of ns2np5 and the following statements:
(i) Elements with this electron configuration are expected to form -1 anions.
(ii) Elements with this electron configuration are expected to have large positive electron affinities.
(iii) Elements with this electron configuration are nonmetals.
(iv) Elements with this electron configuration form acidic oxides.
Which statements are true?
A) (i), (iii,) and (iv) B) (ii) and (iii) C) (i) and (ii) D) (i), (ii), and (iii)
E) All statements are true.
Answer: A
17) Chlorine is much more suitable to exist as an anion than is sodium. This is because __________.
A) chlorine is more metallic than sodium
B) chlorine has a greater electron affinity than sodium does C) chlorine has a greater ionization energy than sodium does D) chlorine is a gas and sodium is a solid
E) chlorine is bigger than sodium Answer: B
18) Alkaline earth metals __________.
A) form basic oxides
B) exist as triatomic molecules C) form monoanions
D) have the smallest atomic radius in a given period E) form halides with the formula MX
Answer: A
19) Which one of the following elements has an allotrope that is produced in the upper atmosphere by lightning?
A) Cl B) N C) O D) S E) He
Answer: C
20) Which of the following does not have eight valence electrons?
A) Rb+1 B) Ti+4 C) Xe D) Cl- E) Sr+1
Answer: E
21) Of the following, __________ cannot accommodate more than an octet of electrons.
A) V B) Ni C) As D) C E) Y
Answer: D
22) There are __________ valence electrons in the Lewis structure of CH3CH2Cl.
A) 20 B) 14 C) 10 D) 12 E) 18
Answer: A
23) Why don't we draw double bonds between the Be atom and the Cl atoms in BeCl2?
A) That would result in the formal charges not adding up to zero.
B) There aren't enough electrons.
C) That would result in more than eight electrons around beryllium.
D) That would result in more than eight electrons around each chlorine atom.
E) That would give positive formal charges to the chlorine atoms and a negative formal charge to the beryllium atom.
Answer: E
24) In the nitrite ion (NO2-), __________.
A) both bonds are single bonds
B) one bond is a double bond and the other is a single bond C) there are 20 valence electrons
D) both bonds are double bonds E) both bonds are the same Answer: E
25) Using the table of average bond energies below, the H for the reaction is __________ kJ.
Bond: C C C-C H-I C-I C-H
D (kJ/mol): 839 348 299 240 413
A) -63 B) +63 C) +160 D) -160 E) -217
Answer: E
