Technetium is an element commonly used in medicine. A technetium atom is represented as ^99 _43 Tc. Give the number of protons, neutrons and electrons in this atom of technetium.

⁹⁹₄₃Tc (how it should be represented in question)
Number of protons = 43 Number of neutrons = 56 Number of electrons = 43
Technetium is given here in nuclear notation. This is where the top number represents the atomic mass, the bottom number represents the atomic number and the letters represent the chemical symbol of the element. Remember that the atomic number equals the number of protons an atom has, whilst the mass number represents the combined number of proteins and neutrons an atom has. Additionally, the number of electrons will be equal to the number of protons in an atom.
Therefore in this question, the atomic number (bottom number) is 43, and therefore the number of protons is 43. The number of electrons is the same as the number of protons, so it is also 43. The atomic mass (top number) is 99, and since the number of protons is 43, the number of neutrons must be = 99 - 43 = 56