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Assignment 02
1- Which formula corresponds to this structure of an aspirin molecule? (In this structure, carbon is
represented as black, hydrogen as gray, and oxygen as red)
a)
b)
c)
d)
e)
C6H7O4
C7H5O3
C9H8O4
C8H5O2
C8H8O4
2- Typically, the mass of an atom of an element in grams is closest to
10−32
10−10
1.
10−22
23
e) 10
a)
b)
c)
d)
3- Naturally occurring neon consists of two isotopes: 20Ne and 22Ne. How many neutrons are in each
isotope ?
a) 20, 22
b) 21, 23
c) 10, 10
d) 11, 13
e) 10, 12
4- Which of the following is a metal?
a) Se
b) Si
c) Sr
d) S
e) P
5- An elemental ion has 22 protons, 20 electrons, and 26 neutrons. Which isotope is it?
a) 48Fe
b) 47Fe
c) 48Ti
d) 48Ti2e) 48Ti2+
6- _____ rays are a stream of fast-moving electrons .
a) Alpha
b) Beta
c) Gamma
d) none of these
7- Which one of the following should be the most similar in chemical properties to strontium?
a) Li
b) At
c) Rb
d) Ba
e) Ga
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8- What is the name for CuS?
a) copper(II) sulfide
b) copper(I) sulfur
c) copper(I) sulfide
d) copper sulfide
e) copper(II) sulfur
9- Which of these acids has a name that begins with hydro-?
a) HCl
b) HClO
c) HClO2
d) HClO3
e) HClO4
10- Elements belonging to which group of the periodic table form ions with a 2+ charge?
a) alkaline earth metals
b) Halogens
c) Chalcogens
d) alkali metals
11- The element zinc consists of five isotopes with masses 63.929, 65.926, 66.927, 67.925, and 69.925 amu.
The relative abundances of these five isotopes are 48.89, 27.81, 4.110, 18.57, and 0.62 percent,
respectively. From these data calculate the average atomic mass of zinc.
a) 63.93 amu
b) 66.93 amu
c) 65.387 amu
d) 65.927 amu
e) 65.39 amu
12- If 60 g of carbon combine with 10 g of hydrogen to form a compound, this means that any sample of this
compound will contain ___ part(s) carbon and ___ part(s) hydrogen by mass.
a) 5, 1
b) 6, 1
c) 1, 1
d) 5, 10
e) 6, 0.17
13- Which pair of symbols below represents isotopes?
a) 16O, 16N
b) 16O, 17O
c) H, He
d) He, He+
e) 13C, 14N
14- An element in the lower left corner of the periodic table
a) is either a metal or metalloid.
b) is definitely a metal.
c) is either a metalloid or a nonmetal.
d) is definitely a nonmetal.
e) is definitely a metalloid.
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15- Which of the following statements is true about the following list of compounds ?
CO2; KCl; KNO3; N2O
a) CO2 is the only molecular compound.
b) CO2 and N2O are the only molecular compounds.
c) KCl, KNO3, and N2O are the only ionic compounds.
d) CO2, KNO3, and N2O are the only molecular compounds.
e) KCl is the only ionic compound.
f) KNO3 is the only ionic compound.
16- Which of the following compounds is not a possible ionic compound?
a) CsCl
b) SrO
c) GaF3
d) Cs2O
e) NaF2
17- A certain number of electrons has a total charge of approximately 1.1 × 10−18 C. How many electrons are
there?
a) 1
b) 2
c) 4
d) 7
e) 11
18- Which ion has the wrong charge?
a) Cs+
b) Ba2+
c) Te2−
d) Xe−
e) I−
19- How many hydrogen atoms are in Co(NH3)6HPO4?
a) 19
b) 6
c) 3
d) 18
e) 4
20- Which one of the following is incorrectly labeled?
a) Mg; alkali metal
b) Ca; alkaline earth metal
c) I; halogen
d) Rn; noble gas
e) Te; chalcogen
21- How many protons and neutrons are there in
a) 43 protons and 55 neutrons
b) 55 protons and 43 neutrons
c) 98 protons and 43 neutrons
d) 43 protons and 98 neutrons
?
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22- Which of the following statements is true for neutral atoms?
a) It is possible for neutral atoms of different elements to have the same number of electrons.
b) The number of neutrons in a neutral atom must always equal the number of protons.
c) The number of neutrons in a neutral atom must always equal the number of electrons.
d) It is possible for neutral atoms of different elements to have the same number of neutrons.
e) It is possible for neutral atoms of different elements to have the same number of protons.
23- Which of the following compounds would you expect to be molecular and not ionic?
a) KCl (potassium chloride, a dietary salt substitute)
b) TiO2 (titanium dioxide, formed in skywriting)
c) ZnS (zinc sulfide, used in photo-sensors)
d) SiC (silicon carbide, an abrasive)
e) CaO (calcium oxide, an acid-neutralizing agent)
24- Which one of the following is named correctly?
a) Ca(HS)2, calcium sulfide
b) HBrO2, bromic acid
c) AlN, aluminum nitride
d) FeO, iron(III) oxide
e) NH4+, ammonia
25- Which of the following ionic formulas is incorrect?
a) Ca(NO2)2
b) Li2CO3
c) Sr2NO3
d) (NH4)2HPO3
e) Hg2(HCO3)2
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