Question

An atom of an element contains 92 electrons and 143 neutrons. what is the mass number of the element

Answer 1

The mass number of an element is the sum of its protons and neutrons. We know that an atom of the element contains 92 electrons, but electrons do not contribute to the mass number. However, we also know that it contains 143 neutrons, which do contribute to the mass number.

The number of protons in an element is also equal to its atomic number, but we don't have that information. However, we can use the fact that the element is electrically neutral, which means it has the same number of protons as electrons. Therefore, the number of protons is also 92.

Adding the number of protons and neutrons, we get:

mass number = number of protons + number of neutrons
mass number = 92 + 143
mass number = 235

So the mass number of the element is 235.

Answer 2

To determine the mass number of the element, we need to add the number of protons and neutrons in the nucleus. Since the number of electrons is equal to the number of protons in a neutral atom, we can calculate the number of protons as:

number of electrons = number of protons = 92

The mass number is the total number of protons and neutrons in the nucleus of an atom. Therefore, the mass number of the element is:

mass number = number of protons + number of neutrons = 92 + 143 = 235

Hence, the mass number of the element is 235.

Step-by-step explanation: