Atomic Structure Quiz Sample Questions
Atomic Structure Quiz
Sample Questions
1. Why do only the number of protons and the number of neutrons make up the atomic mass of an element, but not the electrons?
We generally do not use the number of electrons when calculating the atomic mass of an atom because they weigh so little (precisely 1/1836 AMU), and only in precise calculations are the masses of the electrons included in atomic mass.
2. What was the difference between Mendeleev’s table and Mosley’s new arrangement?
Mendeleev arranged the 63 elements know at his time in order of increasing relative atomic mass, whiles Mosley later order the elements in order of increasing atomic number, or the number of protons in the atom. Mendeleev could not have arranged the elements using Mosley’s method because the concept of protons in the nucleus of an atom was not discovered yet.
3. What are the elements that are located along the zigzag line, and what are their properties?
Metalloids are the elements that touch the zigzag line with the exception of aluminum and polonium, and they have combination of properties of both metals and nonmetals – that is why they are located between the two groups. They cannot be identified either as a metal or a nonmetal.
4. What happens to the reactivity level of elements as you go across each period of the table?
As you go across each period of the Periodic Table of Elements, the reactivity of elements gradually decreases, as the atomic mass increases. The fewer valence electrons an atom holds, the less stable it becomes and the more likely it is to react, which is why elements in the beginning are more reactive.
5. What period of the Periodic Table of Elements are the actinides and lanthanides located?
The lanthanides can be found in the 6th period of the table, while the actinides are in the 7th period. They are isolated from the rest of the elements, and are found underneath the table, in order to save space.
6. A transmits heat and electricity easily.
Conductor
7. What is
Sample Questions
1. Why do only the number of protons and the number of neutrons make up the atomic mass of an element, but not the electrons?
We generally do not use the number of electrons when calculating the atomic mass of an atom because they weigh so little (precisely 1/1836 AMU), and only in precise calculations are the masses of the electrons included in atomic mass.
2. What was the difference between Mendeleev’s table and Mosley’s new arrangement?
Mendeleev arranged the 63 elements know at his time in order of increasing relative atomic mass, whiles Mosley later order the elements in order of increasing atomic number, or the number of protons in the atom. Mendeleev could not have arranged the elements using Mosley’s method because the concept of protons in the nucleus of an atom was not discovered yet.
3. What are the elements that are located along the zigzag line, and what are their properties?
Metalloids are the elements that touch the zigzag line with the exception of aluminum and polonium, and they have combination of properties of both metals and nonmetals – that is why they are located between the two groups. They cannot be identified either as a metal or a nonmetal.
4. What happens to the reactivity level of elements as you go across each period of the table?
As you go across each period of the Periodic Table of Elements, the reactivity of elements gradually decreases, as the atomic mass increases. The fewer valence electrons an atom holds, the less stable it becomes and the more likely it is to react, which is why elements in the beginning are more reactive.
5. What period of the Periodic Table of Elements are the actinides and lanthanides located?
The lanthanides can be found in the 6th period of the table, while the actinides are in the 7th period. They are isolated from the rest of the elements, and are found underneath the table, in order to save space.
6. A transmits heat and electricity easily.
Conductor
7. What is