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Date:
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Atomic Structure (grade 10) B COPY
1.
Which of the following conclusions is consistent with the Bohr model of the atom?
a. Electrons exist in fixed circular paths known as orbits.
b. Electrons are most likely to be located in a space known as an orbital.
c. Electrons are randomly spaced out around a positive mass.
d. Electrons are directly adjacent to the nucleus.
2.
Atoms that lose electrons and have a positive charge are called
.
a. cations
b. anions
c. oxidation numbers
d. none of the above
3.
An atom's valence electrons are those in its
.
a. outermost energy level
b. lowest energy level
c. electron clouds
d. inner energy level
4.
A neutral atom contains 12 neutrons and 11 electrons. What is the number of protons in this atom?
a. 12
b. 23
c. 1
d. 11
5.
A certain isotope of oxygen has 8 protons, 6 neutrons, and 8 electrons. What is its mass number?
a. 8
b. 2
c. 14
d. 22
6.
In which of the following ways do isotopes of the same element differ?
a. in number of protons only
b. in numbers of neutrons and protons
c. in number of neutrons and in mass
d. in number of neutrons only
7.
An atom consists of what key, primary components?
a. ions, protons, electrons
b. protons, electrons, molecules
c. protons, electrons, neutrons
d. elements, neutron protons
8.
9.
Which of the following isotopes has the same number of neutrons as phosphorus-31?
a.
32
S
16
b.
29
Si
14
c.
32
P.
15
d.
28
Si
14
Which of the following pairs shows isotopes of the same element?
a. 12
6 C
and
12C
6
b. 14
6 C
and
14N
7
c. 14
6 C
and
12C
6
d. 14
6 C
and
14C −4
6
10. Negatively-charged ions are called
a. anions.
b. cations.
c. electrons.
d. protons.
11. What is true about the following element?
a. It gains 3 valence electrons to form an ion.
b. It loses 5 valence electrons to form an ion.
c. It loses 3 valence electrons to form an ion.
d. It gains 5 valence electrons to form an ion.
12. 72.2% of element
element X?
a. 86.0 g
b. 85.6 g
c. 86.4 g
d. 85.0 g
e. You can't tell
X is mass number 85. 27.8% is mass number 87. What is the average atomic mass of
13. Look at the electron-dot diagram for magnesium.
An atom of magnesium would be most likely to bond with an atom of which of the following elements?
a.
b.
c.
d.
14. An atom's number of protons and atomic number never change.
a. True
b. False
15. Electrons in the outermost shell of an atom are called
a. electrons.
b. molecules.
c. valence electrons.
d. atoms.
16. An ionic bond is the attraction between
a. similarly charged ions
b. oppositely charged ions
c. neutral ions
d. neutral atoms
.
17. Aluminum atoms tend to react to form
a.
3+
b.
1+
c.
5−
d.
3−
ions.
18. Imagine that a new element has been discovered, which has the chemical symbol Rx. The isotope Rx-298
has a mass of 298 amu and an abundance of 75%. The isotope Rx-299 has a mass of 299 amu and an
abundance of 25%. Which of the following values is closest to the average atomic mass of this element,
Rx?
a. 298 amu
b. 299 amu
c. 300 amu
d. 301 amu
19. How many protons and electrons are in a
Cu+2 ion?
a. 27 protons, 29 electrons
b. 27 protons, 31 electrons
c. 29 protons, 27 electrons
d. 29 protons, 31 electrons
20. Which electron-dot diagram shows an alkali metal?
a.
b.
c.
d.
21. Look at the electron-dot diagram for hydrogen.
An atom of hydrogen would be most likely to bond with an atom of which of the following elements?
a.
b.
c.
d.
22. Which of the following is an ion?
a.
Na−
b. Cl
c.
Hg+
d. K
e. A & C
f. B & D
23. What is the mass number of an atom with 11 protons, 11 electrons, and 12 neutrons?
a. 11
b. 23
c. 22
d. 1
24. An
is the smallest unit of an element and has all the properties of an element.
a. element
b. electron
c. atom
d. ion
25. What is the total number of electrons in a
Cr3+ ion?
a. 21
b. 18
c. 24
d. 27
26. Mg has three different isotopes. Mg-24 has an abundance of 78.70%, Mg-25 has an abundance of 10.13%,
and Mg-26 has an abundance of 11.17%. Which setup is correct for calculating the atomic mass of
magnesium?
a. (78.70)(24 u)+(10.13)(25 u)+(11.17)(26 u)
b. (78.70)(24 u)+(11.17)(25 u)+(10.13)(26 u)
c. (0.7870)(24 u)+(0.1013)(25 u)+(0.1117)(26 u)
d. (0.7870)(24 u)+(0.1117)(25 u)+(0.1013)(26 u)
27. The chemical name for table salt is sodium chloride, or simply NaCl. What type of chemical is NaCl?
a. Compound
b. Element
c. Molecule
d. Ion
28. The chemical properties of an atom and the types of bonds it may make are primarily determined by the
number of
a. neutrons it has in its nucleus.
b. protons it has in its nucleus.
c. energy levels it has.
d. electrons it has in its outermost energy level.
29. When an atom loses electrons it becomes
a. negatively
b. ionically
c. covalently
d. positively
30. Which combination of particle and charge is correct?
a. electron: no charge
b. proton: positively charged
c. electron: positively charged
d. neutron: negatively charged
charged.
31. The image shows the electron-dot diagram for a neutral hydrogen atom.
a. True
b. False
32. Which of the following atoms has the fewest electrons?
a. 127
53 I
b. 128
52 Te
c. 123
51 Sb
d. 121
50 Sn
33. What do you include in the Bohr-Rutherford diagrams?
a. protons
b. neutrons
c. all electrons
d. all of the above
34. The isotopes of nitrogen have masses of 14 amu and 15 amu. The average atomic mass of nitrogen is
14.01 amu. Based on this information, the most abundant isotope of nitrogen has a mass of
.
a. 15 amu
b. 16 amu
c. 14 amu
d. 13 amu
35. What is the total number of protons in an ion with 10 electrons, a charge of +2, and an atomic number of
12?
a. 10
b. 9
c. 12
d. 2
36. If an atom loses a valence electron, what will happen?
a. The charge of the atom does not change because an electron has no charge.
b. The atom will lose the same amount of protons to keep the charge neutral.
c. The atom will become positively charged because it has lost an electron.
d. The atom will become negatively charged because it has lost an electron.
37. Group 17 elements, the halogens, are the most reactive of the nonmetals because they
a. require only one electron to fill their outer energy level.
b. have the highest ionization energies.
c. have the largest atomic radii.
d. are the farthest to the right in the periodic table.
38. An atom with a charge is known as an
.
a. isotope
b. isomer
c. element
d. ion
39. Which of the following is the best definition of a proton?
a. A negatively charged particle found in the nucleus.
b. A particle that has no charge, but is found in the nucleus.
c. A positively charged particle found in the nucleus.
d. A positively charged particle found in the orbits.
40. The subatomic particle that plays the greatest role in determining properties and reactivity of an element is
the
a. proton.
b. electron.
c. neutron.
d. nucleus.
41. Which represents a noble gas?
a.
b.
c.
d.
42. Which element has an atom with the electron configuration 2-8-1?
a. magnesium
b. sodium
c. calcium
d. beryllium
43. If an atom of calcium has a charge of +2, how many protons, neutrons, and electrons does it have?
a. 20 protons, 40 neutrons, and 16 electrons
b. 20 protons, 20 neutrons, and 18 electrons
c. 20 protons, 20 neutrons, and 22 electrons
d. 20 protons, 40 neutrons, and 18 electrons
44. Four electron-dot diagrams as shown below. Which of these elements is the least likely to bond with
another atom?
a.
b.
c.
d.
45. The
is the basic unit of matter which is where the study of chemistry begins.
a. cell
b. matter
c. atom
d. photons
46. What is the charge of the nucleus of a magnesium-24 atom?
a. +2
b. +24
c. +12
d. +36
47. Kayla draws the image shown as part of her physical science homework.
What did Kayla draw?
a. Bohr model
b. Lewis structure
c. Molecular formula
d. Structural formula
48. What is the total number of neutrons in an atom of Li-7?
a. 7
b. 3
c. 1
d. 4
49. Which feature of the electron configuration determine the chemical properties of an element?
a. Its total number of electrons
b. The number of electrons in the first shell
c. The number of valence electrons
d. The number of electrons in the second shell