Positive ions, also called cations, are formed from neutral atoms by the loss of which type of subatomic particles?

Introduction / Context:
Atoms are made up of three main types of subatomic particles, namely protons, neutrons, and electrons. When atoms gain or lose charged particles, they can form ions. Positive ions are called cations, and negative ions are called anions. This question asks which particle must be lost when a neutral atom changes into a positively charged ion. Understanding this process is essential in basic chemistry, especially in topics like ionic bonding, electrolysis, and redox reactions.

Given Data / Assumptions:

• A neutral atom has equal numbers of protons and electrons so that the total charge is zero.
• Positive ions have a net positive charge.
• Available subatomic particles in the options are neutrons, protons, nuclear charge, and electrons.
• We assume that the nucleus remains intact in ordinary chemical processes.

Concept / Approach:
The overall charge of an atom is determined by the balance between positively charged protons in the nucleus and negatively charged electrons in shells around the nucleus. Neutrons carry no charge. In most chemical changes, the nucleus and its protons remain unchanged, while electrons can be transferred or shared. To form a positive ion from a neutral atom, the atom must lose negative charge so that positive charge dominates. That means electrons are removed. Losing electrons produces a cation with a net positive charge equal to the number of electrons lost.

Step-by-Step Solution:
Step 1: Consider a neutral atom with Z protons and Z electrons, so total charge is zero. Step 2: To obtain a net positive charge, the atom must have fewer negative charges than positive charges. Step 3: Chemical changes usually involve the movement of electrons, not protons or neutrons, which remain locked in the nucleus. Step 4: If the atom loses one or more electrons, it will still have the same number of protons, but fewer electrons. Step 5: The resulting species has excess positive charge and is called a positive ion or cation. Therefore, loss of electrons is responsible.

Verification / Alternative check:
Take a simple example of sodium. A neutral sodium atom has 11 protons and 11 electrons. If it loses one electron to form Na plus, it now has 11 protons and only 10 electrons. The net charge is plus one because positive charges exceed negative charges by one unit. This process does not involve any change in the number of neutrons or protons. Similar reasoning applies to other common cations such as Ca two plus or Al three plus, where the atom has lost two or three electrons respectively. This confirms that the correct answer is electrons.

Why Other Options Are Wrong:
Neutrons carry no electric charge, so gaining or losing neutrons changes the mass and isotope of an atom, not its charge; option neutrons is wrong. Protons are positively charged, but chemical reactions do not usually remove them from the nucleus, and losing protons would change the element identity; so option protons is incorrect for normal ion formation. The phrase nuclear charge is vague and not a specific particle; in chemical ion formation the nucleus remains unchanged, so this option is also wrong. Only loss of electrons explains the formation of a positive ion from a neutral atom.

Common Pitfalls:
Some learners confuse the roles of protons and electrons and may think that a positive ion is created by gaining protons. Others may assume that any change in particles inside the atom can produce charge. To avoid such mistakes, remember that in ordinary chemistry the nucleus stays the same and electrons are the particles that move. Positive ions form when an atom loses electrons, while negative ions form when an atom gains electrons.

Final Answer:
Positive ions or cations are formed from neutral atoms by the loss of electrons.