What is an atom like? P2 5.1 (AQA GCSE Physics)

A helium atom has two protons, two neutrons and two electrons

A helium atom has four protons, two neutrons and two electrons

A helium atom has two protons, four neutrons and two electrons

If an atom of chlorine gained one electron then it would have an overall positive charge. It is said that it has become an ion.

If an atom of chlorine gained one electron then it would have an overall negative charge. It is said that it has become an ion.

It will have 92 electrons because in an atom the number of protons is always equal to the number of electrons to make the overall charge of the atom neutral. It will also have 146 neutrons because the mass number (238) is the total number of protons and neutrons (particles) in an atom's nucleus.

It will have 92 neutrons because in an atom the number of protons is always equal to the number of neutrons to make the overall charge of the atom neutral. It will also have 146 electrons because the mass number (238) is the total number of protons and electrons (particles) in an atom's nucleus.

You can't tell because the atom could have lost or gained electrons and neutrons.

Uranium-235 has a mass number of 235 and also has 92 protons. The mass number of an atom is the total number of protons and neutrons (particles) in the nucleus of an atom. Therefore, to find out the number of neutrons in the nucleus you must subtract 235 from 92 which equals -143 (the number of neutrons in the nucleus of the atom). By contrast uranium-238 has a mass number of 238 so to find out number of neutrons you must perform the following calculation: 92 -238 = -146. Therefore, we can conclude that the difference between the two atoms of uranium is that there is three more neutrons in the nucleus of uranium-235.

Uranium-235 has a mass number of 238 and also has 92 protons. The mass number of an atom is the total number of protons and neutrons (particles) in the nucleus of an atom. Therefore, to find out the number of neutrons in the nucleus you must subtract 92 from 238 which equals 146 (the number of neutrons in the nucleus of the atom). By contrast uranium-238 has a mass number of 238 so to find out number of neutrons you must perform the following calculation: 235 - 92 = 143. Therefore, we can conclude that the difference between the two atoms of uranium is that there is three more neutrons in the nucleus of uranium-235.

Uranium-235 has a mass number of 235 and also has 92 protons. The mass number of an atom is the total number of protons and neutrons (particles) in the nucleus of an atom. Therefore, to find out the number of neutrons in the nucleus you must subtract 92 from 235 which equals 143 (the number of neutrons in the nucleus of the atom). By contrast uranium-238 has a mass number of 238 so to find out number of neutrons you must perform the following calculation: 238 - 92 = 146. Therefore, we can conclude that the difference between the two atoms of uranium is that there is three more neutrons in the nucleus of uranium-238.