Question

Use the atomic number, atomic mass, and symbol of the elements to indicate the number of subatomic particles in an atom of the following elements __

a) Electrons in oxygen.
b) Electrons in Li.
c) Protons in Na.
d) Protons in helium.

Answer 1

The number of electrons or protons in an atom can be determined by the atomic number. Oxygen has 8 electrons, lithium has 3 electrons, sodium has 11 protons, and helium has 2 protons.

Step-by-step explanation:

To determine the number of subatomic particles in an atom of a given element, we need to use the atomic number and atomic mass of the element. The atomic number equals the number of protons, and in a neutral atom, it also equals the number of electrons. The atomic mass is the sum of the protons and neutrons.

a) Electrons in oxygen: Oxygen has the symbol O and an atomic number of 8. Therefore, an oxygen atom has 8 electrons.

b) Electrons in Li (Lithium): Lithium has the symbol Li and an atomic number of 3. Thus, a lithium atom has 3 electrons.

c) Protons in Na (Sodium): Sodium's symbol is Na, and it has an atomic number of 11. Consequently, a sodium atom contains 11 protons.

d) Protons in helium: Helium has the symbol He and an atomic number of 2, meaning a helium atom has 2 protons.