Question

How many protons, neutrons, and electrons are there in a neutral atom of 240 Am (americium- 240 )?

Answer 1

A neutral atom of americium-240 has 95 protons, 95 electrons, and 145 neutrons. The atomic number indicates the number of protons and electrons while the mass number minus the atomic number gives the number of neutrons.

Step-by-step explanation:

In a neutral atom of americium-240 (240 Am), there is an equal number of protons and electrons, since the overall charge is neutral. The atomic number of americium (Am) is 95, which also represents the number of protons. Since it is neutral, there are also 95 electrons. The mass number of 240 represents the sum of protons and neutrons. To find the number of neutrons, you subtract the number of protons from the mass number, which in this case is 240 - 95 = 145 neutrons.

Answer 2

120 protons, 120 neutrons, 120 electrons

Step-by-step explanation:

The number written next to element (americium - 240) is the mass number. The mass number consists of all the protons and neutrons within an atom of a particular element. Assuming that this atom is not an isotope (atoms of the same element with different number of neutrons), there should be an equal amount of protons and neutrons.

Therefore, if the mass number is 240, there should be 120 protons and 120 neutrons in the atom (240 / 2 = 120).

In neutral atoms, there is an equal amount of positively charged protons and negatively charged electrons. As such, if there are 120 protons, there should be 120 electrons.