1.
Li, Na and K belong to the _________________ family.
Correct Answer
B. Alkali Metals
Explanation
Li, Na, and K belong to the Alkali Metals family because they all have similar properties and characteristics. Alkali Metals are highly reactive metals that are located in Group 1 of the periodic table. They have one valence electron, making them highly reactive and easily losing that electron to form a positive ion. Li, Na, and K all have one valence electron and exhibit similar chemical behaviors, such as reacting vigorously with water and oxygen. Therefore, they are classified as Alkali Metals.
2.
The atomic number is equal to the number of ________________.
Correct Answer
B. Protons
Explanation
The atomic number is a fundamental property of an element that defines its identity. It is equal to the number of protons found in the nucleus of an atom of that element. Protons are positively charged particles, and the number of protons determines the element's chemical properties and its position in the periodic table. For example, all carbon atoms have 6 protons, while all oxygen atoms have 8 protons.
3.
If the atomic mass of an element is 12.01 and the atomic number is 6, how many neutrons are in atom of this element?
Correct Answer
B. 6
Explanation
The atomic mass of an element represents the sum of the protons and neutrons in the atom. The atomic number represents the number of protons in the atom. To find the number of neutrons, we subtract the atomic number from the atomic mass. In this case, the atomic mass is 12.01 and the atomic number is 6, so the number of neutrons is 12.01 - 6 = 6.
4.
Electrons in the outermost energy level of an atom are the ______________ electrons.
Correct Answer
B. Valence
Explanation
Valence electrons are the electrons in the outermost energy level of an atom. These electrons are involved in the formation of chemical bonds and determine the reactivity and bonding behavior of an atom. They are responsible for the atom's ability to gain, lose, or share electrons with other atoms to achieve a stable electron configuration. Therefore, the correct answer is "valence."
5.
As you move down the periodic table in a family the valence electrons do not change.
Correct Answer
A. True
Explanation
As you move down the periodic table in a family, the number of valence electrons remains the same. This is because elements in the same family have the same number of valence electrons, which are the electrons in the outermost energy level of an atom. The number of valence electrons determines an element's chemical properties and reactivity. Therefore, it is true that as you move down the periodic table in a family, the valence electrons do not change.
6.
As you move across the periodic table from left to right the valence electrons stay the same.
Correct Answer
B. False
Explanation
As you move across the periodic table from left to right, the number of valence electrons increases. Valence electrons are the electrons in the outermost energy level of an atom, and they determine the chemical properties and reactivity of an element. In general, elements on the left side of the periodic table have fewer valence electrons, while elements on the right side have more valence electrons. Therefore, the statement that the valence electrons stay the same as you move across the periodic table from left to right is false.
7.
How many neutrons are in an atom of Hydrogen?
Correct Answer
C. Zero
Explanation
An atom of hydrogen typically consists of one proton and one electron. Neutrons are neutral particles found in the nucleus of an atom, but hydrogen atoms usually do not have any neutrons. Therefore, the correct answer is zero.
8.
Predict whether the following is an ionic bond or covalent bond.
O (oxygen) and O (oxygen)
Correct Answer
B. Covalent bond
Explanation
The given pair of elements, oxygen and oxygen, form a covalent bond. Covalent bonds occur when atoms share electrons to achieve a stable electron configuration. In this case, both oxygen atoms need two additional electrons to fill their outermost shell, so they share two electrons with each other. This sharing of electrons creates a strong bond between the two oxygen atoms, resulting in a covalent bond.
9.
A neutron has a ________________ charge.
Correct Answer
B. Neutral
Explanation
A neutron has a neutral charge because it does not have a positive or negative charge. Neutrons are subatomic particles found in the nucleus of an atom, along with protons. While protons have a positive charge and electrons have a negative charge, neutrons have no charge at all. This means that they are not attracted to or repelled by electric fields, making them electrically neutral.
10.
The electron is located in _______________.
Correct Answer
B. Electron cloud around nucleus
Explanation
The electron is located in the electron cloud around the nucleus. This is because electrons are negatively charged particles that orbit around the positively charged nucleus in an atom. The electron cloud represents the region where the electron is most likely to be found, and it consists of different energy levels or orbitals. The electron cloud provides a probabilistic description of the electron's position, as electrons do not have fixed orbits but rather exist in a state of constant motion within the cloud.
11.
The mass of a proton is over __________________ greater than the mass of an electron.
Correct Answer
B. 1,823 times
Explanation
The mass of a proton is significantly larger than the mass of an electron. In fact, the mass of a proton is over 1,823 times greater than the mass of an electron. This means that protons are much heavier compared to electrons.
12.
The 2-8-8 octet rule means: (choose the best answer)
Correct Answer
C. There are two electrons in the first energy level, a maximum of eight electrons in the second and third energy levels
Explanation
The 2-8-8 octet rule refers to the arrangement of electrons in the electron cloud. It states that the first energy level can hold up to 2 electrons, while the second and third energy levels can hold a maximum of 8 electrons each. This rule helps to explain the stability of atoms, as atoms tend to gain, lose, or share electrons in order to achieve a full outer shell of 8 electrons.