Question

An electrically charged atom or a group of atoms is known as:
(A) A meson
(B) A proton
(C) An ion
(D) A cyclotron

Answer 1

Hint: Being electrically charged always means that the balance of charge in any substance is disrupted. In case of an atom, it is nothing but the electrically charged particles-protons and electrons, which lose their equilibrium state. That is, the number of protons is greater than the number of electrons or vice versa.

Complete Step by Step answer
We know that all the substances in this universe are made up of tiny particles called the atoms. Although atoms were considered the basic and smallest building blocks of every substance, it was proven wrong and later it was discovered that there are subatomic particles called -protons, electrons and neutrons in which protons and neutrons are electrically charged. These particles co-exist within an atom such that they maintain an equilibrium state. Thus, making the atom neutral and stable.
When this stable state or neutral state is lost, atoms tend to have a greater number of protons or a greater number of electrons. We know that electrons are negatively charged particles and protons are positively charged particles. So, if the number of electrons is more than the atoms becomes negatively charged and when the number of protons exceed the number of electrons then the atom is positively charged. The imbalance can be due to collision, or any other way in which energy is passed to the atoms. In this state the atom attracts other charges so as to get the atom back to its stable/ neutral state. Such charged atoms that tend to have an unequal number of protons and electrons are charged and hence are called IONS. If the ion has a positive charge it is attracted towards negatively charged particles and are called cations. If the ion is negatively charged then it is called an anion.
Thus, an electrically charged atom is called an ion.

Note
Out of the other particles in the option, Meson is a subatomic particle that is said to consist of 2 quarks while cyclotron is a type of particle accelerator and not a subatomic particle. We know that a proton is a positively charged subatomic particle.