Honors Chem Unit 3 (practice test)
Exam 2025 Questions and Answers
Which group of elements in the periodic table is known as the alkali metals -
ANSWER-1A
Which group of elements in the periodic table is known as the alkaline earths -
ANSWER-2A
Which group of elements in the periodic table is known as the halogens -
ANSWER-7A
Which group of elements in the periodic table is known as the noble gases -
ANSWER-8A (or 0A)
Which group in the periodic table is known as the chalcogens - ANSWER-6A
Give an example of a region of the periodic table that acts as a bridge between two
other regions. What does this tell you about the properties of the bridging elements
- ANSWER-The metalloids are between the metals and nonmetals. The properties
of metalloids are intermediate (between) metals and nonmetals, i.e.
semiconductors.
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,The transition metals act can be considered where the elements start changing
from metallic character to nonmetallic character - or transitioning between metals
and nonmetals.
In terms of the periodic law, explain which two of these elements are most similar:
sodium (element 11), phosphorus (element 15), and sulfur (element 16). -
ANSWER-Their locations in the periodic table indicate that phosphorus and sulfur
are nonmetals and sodium is a metal. Nonmetals are a group with characteristic
properties, so phosphorus and sulfur are the most similar elements of the three.
What can you predict about the properties of xenon and helium, both in Group 18
(VIIIA) in the periodic table? Why? - ANSWER-In the periodic table, elements in
the same column or group have similar properties. Because helium and xenon are
in the same group, they have similar properties. They are both noble gases
About what percent of elements is classified as metals - ANSWER-about 80% of
the elements are metals
The s and p sub-levels of an atom of an element in period 3 are filled with
electrons. Which orbitals are filled in this atom - ANSWER-1s, 2s, 2p, 3s, 3p
From which orbital in a lithium atom is an electron transferred to form Li+ -
ANSWER-s2
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, What orbital is filled when iodine gains an electron to become a negative ion -
ANSWER-5p orbital
In which group in the periodic table do the elements have the highest
electronegativity values - ANSWER-Halogens (non-metals too but halogens is the
most)
Xenon is generally un-reactive. How is its low reactivity related to its position in
the periodic table? - ANSWER-Xenon is whats known as a noble gas, all noble
gases tend to have low reactivity
The periodic law - ANSWER-When the elements are arranged in order of
increasing atomic mass, certain sets of properties recur periodically (at predictable,
recurring intervals).
The octet rule applies to atoms within compounds as well as individual atoms.
Elements unite to form a more stable configuration. How is this stability shown in
the case of sodium and chlorine combining to form sodium chloride? - ANSWER-
Sodium wants to lose 1 electron to achieve a stable noble gas configuration.
Chlorine wants to gain an electron to achieve a stable noble gas configuration.
Sodium can lose it's electron to chlorine - thus, sodium chloride
In our class we observed that even though lithium and potassium are both
elements in Group IA, potassium reacts more vigorously with water than lithium.
Using your understanding of the determining factors for periodic trends, explain
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Exam 2025 Questions and Answers
Which group of elements in the periodic table is known as the alkali metals -
ANSWER-1A
Which group of elements in the periodic table is known as the alkaline earths -
ANSWER-2A
Which group of elements in the periodic table is known as the halogens -
ANSWER-7A
Which group of elements in the periodic table is known as the noble gases -
ANSWER-8A (or 0A)
Which group in the periodic table is known as the chalcogens - ANSWER-6A
Give an example of a region of the periodic table that acts as a bridge between two
other regions. What does this tell you about the properties of the bridging elements
- ANSWER-The metalloids are between the metals and nonmetals. The properties
of metalloids are intermediate (between) metals and nonmetals, i.e.
semiconductors.
COPYRIGHT ©️ 2025 ALL RIGHTS RESERVED...TRUSTED & VERIFIED 1
,The transition metals act can be considered where the elements start changing
from metallic character to nonmetallic character - or transitioning between metals
and nonmetals.
In terms of the periodic law, explain which two of these elements are most similar:
sodium (element 11), phosphorus (element 15), and sulfur (element 16). -
ANSWER-Their locations in the periodic table indicate that phosphorus and sulfur
are nonmetals and sodium is a metal. Nonmetals are a group with characteristic
properties, so phosphorus and sulfur are the most similar elements of the three.
What can you predict about the properties of xenon and helium, both in Group 18
(VIIIA) in the periodic table? Why? - ANSWER-In the periodic table, elements in
the same column or group have similar properties. Because helium and xenon are
in the same group, they have similar properties. They are both noble gases
About what percent of elements is classified as metals - ANSWER-about 80% of
the elements are metals
The s and p sub-levels of an atom of an element in period 3 are filled with
electrons. Which orbitals are filled in this atom - ANSWER-1s, 2s, 2p, 3s, 3p
From which orbital in a lithium atom is an electron transferred to form Li+ -
ANSWER-s2
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, What orbital is filled when iodine gains an electron to become a negative ion -
ANSWER-5p orbital
In which group in the periodic table do the elements have the highest
electronegativity values - ANSWER-Halogens (non-metals too but halogens is the
most)
Xenon is generally un-reactive. How is its low reactivity related to its position in
the periodic table? - ANSWER-Xenon is whats known as a noble gas, all noble
gases tend to have low reactivity
The periodic law - ANSWER-When the elements are arranged in order of
increasing atomic mass, certain sets of properties recur periodically (at predictable,
recurring intervals).
The octet rule applies to atoms within compounds as well as individual atoms.
Elements unite to form a more stable configuration. How is this stability shown in
the case of sodium and chlorine combining to form sodium chloride? - ANSWER-
Sodium wants to lose 1 electron to achieve a stable noble gas configuration.
Chlorine wants to gain an electron to achieve a stable noble gas configuration.
Sodium can lose it's electron to chlorine - thus, sodium chloride
In our class we observed that even though lithium and potassium are both
elements in Group IA, potassium reacts more vigorously with water than lithium.
Using your understanding of the determining factors for periodic trends, explain
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