For an atom to be considered "neutral," it must have an equal number of protons and electrons. Protons have a positive charge, while electrons have a negative charge. When these charges are balanced, the overall charge of the atom is zero, making it neutral.
Question 2
In order for an atom to be considered "neutral", which of the following must be true?
11 answers
A student looks up an element on the periodic table. The table says that the atomic number of the element is 12 and the mass number of the element is 40. What information do these two numbers convey about the element?
a
The element has 40 protons and 12 neutrons
b
The element has 12 protons and 12 neutrons
c
The element has 12 protons and has 28 neutrons
d
The element has 28 protons and 40 neutrons
a
The element has 40 protons and 12 neutrons
b
The element has 12 protons and 12 neutrons
c
The element has 12 protons and has 28 neutrons
d
The element has 28 protons and 40 neutrons
The atomic number of an element is the number of protons it has. In this case, the atomic number is 12, which means the element has 12 protons.
The mass number is the sum of the protons and neutrons in the nucleus of an atom. In this case, the mass number is 40.
To find the number of neutrons, you can use the formula:
\[ \text{Neutrons} = \text{Mass Number} - \text{Atomic Number} \]
So, for this element:
\[ \text{Neutrons} = 40 - 12 = 28 \]
Therefore, the element has 12 protons and 28 neutrons.
The correct answer is:
c The element has 12 protons and has 28 neutrons.
In order for an atom to be considered "neutral", which of the following must be true?
a
The number of protons and neutrons must be the same
b
The number of protons and electrons must be the same
c
There are more protons than electrons
d
There are more neutrons than protons
a
The number of protons and neutrons must be the same
b
The number of protons and electrons must be the same
c
There are more protons than electrons
d
There are more neutrons than protons
For an atom to be considered "neutral," the correct statement is:
b The number of protons and electrons must be the same.
This balance ensures that the positive charges from the protons are canceled out by the negative charges from the electrons, resulting in a neutral atom. The number of neutrons does not affect the overall charge of the atom, so options a, c, and d are not correct in the context of the atom being neutral.
In all elements in a group, the thing that is the same is the:
a
Number of electrons in the valence shell
b
Number of electrons
c
Number of protons
d
Number of neutrons
a
Number of electrons in the valence shell
b
Number of electrons
c
Number of protons
d
Number of neutrons
In all elements in a group of the periodic table, the thing that is the same is the:
a Number of electrons in the valence shell.
Elements in the same group (or column) have similar chemical properties because they have the same number of valence electrons, which are the electrons in the outermost shell. This is what largely determines how an element behaves in chemical reactions. The number of protons (option c) differs among the elements in a group, as the atomic number increases down the group. Similarly, the number of neutrons (option d) can vary as well. Thus, option a is the correct choice.
Two of most unique elements on the periodic table are hydrogen and helium. What makes them so unique and removed from the other groups on the periodic table?
a
Unlike all other elements, hydrogen and helium are gases
b
Unlike all other elements, hydrogen and helium are not considered metals
c
Unlike all other elements, hydrogen and helium only have a maximum of 2 valence electrons
d
Unlike all other elements, hydrogen and helium have very limited properties
a
Unlike all other elements, hydrogen and helium are gases
b
Unlike all other elements, hydrogen and helium are not considered metals
c
Unlike all other elements, hydrogen and helium only have a maximum of 2 valence electrons
d
Unlike all other elements, hydrogen and helium have very limited properties
The most accurate statement that explains what makes hydrogen and helium unique on the periodic table is:
c Unlike all other elements, hydrogen and helium only have a maximum of 2 valence electrons.
- Hydrogen has one electron in its outer shell, so it can hold a maximum of 2 electrons.
- Helium has two electrons in its outer shell, which fills its valence shell, making it stable.
In contrast, most other elements can have more than 2 valence electrons depending on their group. While option a (they are gases) is true, there are other elemental gases, and while option b (not considered metals) is also correct, it does not capture the unique aspect in the context of their electronic structure. Lastly, option d is too vague and not entirely accurate. Therefore, option c is the best choice.
The periodic table groups elements into which of the following three categories?
a
Solids, Liquids, Gases
b
Heavy, Light, Medium
c
Dense, Expanded, Compressed
d
Metals, Nonmetals, Metalloids
a
Solids, Liquids, Gases
b
Heavy, Light, Medium
c
Dense, Expanded, Compressed
d
Metals, Nonmetals, Metalloids
The periodic table groups elements into the following three categories:
d Metals, Nonmetals, Metalloids.
These categories help to classify the elements based on their properties. Metals are typically good conductors of heat and electricity, nonmetals have varied properties and are generally poor conductors, and metalloids have properties that are intermediate between metals and nonmetals.
The other options listed (solids, liquids, gases; heavy, light, medium; dense, expanded, compressed) do not accurately represent the primary classification used in the periodic table.
1 answer