Atoms having the same ...... but different ...... are called isotopes.

Q: What exactly is an isotope?

An isotope is a variant of a chemical element. While all isotopes of a given element share the same number of protons (atomic number), they differ in the number of neutrons, which gives them different mass numbers.

Q: Do isotopes of an element have the same chemical properties?

Yes, for the most part! Chemical properties are determined by the number of electrons, which is equal to the number of protons in a neutral atom. Since isotopes have the same number of protons, their chemical behavior is almost identical.

Q: Why do isotopes have different mass numbers?

The mass number is the sum of protons and neutrons. Since isotopes of the same element have different numbers of neutrons, their total mass numbers naturally differ.

Q: Can isotopes of an element have different atomic numbers?

Absolutely not. The atomic number is the defining characteristic of an element. If you change the atomic number (number of protons), you change the element entirely.

Q: What are some common examples of isotopes?

Carbon-12 and Carbon-14 are classic examples. Both have 6 protons, but Carbon-12 has 6 neutrons while Carbon-14 has 8 neutrons. Carbon-14 is radioactive and is used in carbon dating.

Question

Atoms having the same ...... but different ...... are called isotopes.

Sigma Percentile · Accepted Answer

### The Architecture of an Atom

To understand isotopes, we must first journey into the heart of an atom. Imagine an atom as a miniature solar system. At its very center lies a dense core called the **nucleus**, which houses positively charged **protons** and neutral **neutrons**.

Orbiting this nucleus are the negatively charged **electrons**.

The identity of an element is strictly determined by the number of protons in its nucleus. This fundamental quantity is known as the **atomic number** ($Z$). For instance, every atom in the universe with exactly one proton is hydrogen, and every atom with exactly six protons is carbon.

### The Mass of an Atom

While protons define the element, neutrons play a crucial role in determining the atom's mass. The total count of protons and neutrons combined is called the **mass number** ($A$).

Mathematically, it is expressed as:

$$A = Z + N$$

where $N$ is the number of neutrons. Since electrons have a negligible mass compared to protons and neutrons, the mass number $A$ gives us a very close approximation of the atom's total atomic mass.

### The Concept of Isotopes

Here is where nature introduces a fascinating twist. While all atoms of a specific element must have the exact same number of protons (same $Z$), they do not necessarily need to have the same number of neutrons.

Atoms of the same element that contain different numbers of neutrons are called **isotopes**. Because they have the same atomic number, they belong to the same element and exhibit nearly identical chemical properties.

However, because their neutron counts differ, their mass numbers ($A$) are different. This difference in mass can lead to variations in physical properties, such as density or stability (radioactivity).

### A Classic Example: Hydrogen

Let's look at the simplest element, hydrogen. It has three well-known isotopes:

1. **Protium** ($^1_1	ext{H}$): The most common form, with 1 proton and 0 neutrons.
2. **Deuterium** ($^2_1	ext{H}$): Contains 1 proton and 1 neutron.
3. **Tritium** ($^3_1	ext{H}$): Contains 1 proton and 2 neutrons, making it radioactive.

All three are hydrogen because they all have an atomic number of 1. But their mass numbers are 1, 2, and 3, respectively.

### Final Conclusion

Returning to our original statement, we can now confidently fill in the blanks.

Atoms having the same **atomic number** but different **mass number** are called isotopes.

Animated Solution for Physics - Atoms and Nuclei: Atoms having the same ...... but different ...... are called isotopes.

Visualized Solution

Atomic Structure

Atomic Number ( $Z$ )

Mass Number ( $A$ )

Concept of Isotopes

Isotopes Definition

Final Answer

Examples of Isotopes

The Sigma Insight: Nucleus and Nuclear Reaction

The Architecture of an Atom

The Mass of an Atom

The Concept of Isotopes

A Classic Example

Final Conclusion

Similar Questions

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List-I

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Comprehension Passage

The correct statement is

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