# What is Atomic Mass? | Infinity Learn | Summary and Q&A

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August 8, 2018
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Infinity Learn NEET
What is Atomic Mass? | Infinity Learn

## TL;DR

Atomic mass is the total mass of protons and neutrons present in an atom's nucleus.

## Key Insights

• 💆 Atomic mass is the sum of proton and neutron masses and is also known as the mass number.
• 🫀 Isotopes are atoms of the same element with different numbers of neutrons.
• 🫀 Isotopes can have different atomic masses.
• 🫀 Atomic mass has no effect on the charge of an atom.
• 🫀 An element can have different isotopes with different atomic masses.
• 🫀 The atomic mass of an element is calculated by considering the masses of its isotopes and their relative abundance.
• 🫀 Isotopes of an element have the same atomic number but different atomic masses.

## Transcript

In the previous video we have seen how atomic mass is measured. Now let us understand atomic mass in detail. Before that, can you tell me what exactly the concept of Atomic Number is? Can you define it once for me? Yes! It is simply the number of protons present inside the nucleus of an atom. Now on similar lines, can you tell me what atomic mass c... Read More

### Q: What is the concept of atomic number?

Atomic number is simply the number of protons present in the nucleus of an atom.

### Q: How is atomic mass determined?

Atomic mass is calculated by adding the masses of protons and neutrons in the atom's nucleus.

### Q: Why are electrons considered to have negligible mass?

Electrons have a very small mass compared to protons and neutrons, hence they are considered almost weightless.

### Q: How is atomic mass affected by the presence of extra neutrons?

The presence of extra neutrons does not affect the charge of the atom, so the atomic mass is not affected.

## Summary & Key Takeaways

• Atomic mass is the mass of an atom, calculated by adding the masses of protons and neutrons in the nucleus.

• Protons and neutrons have significant mass, while electrons are considered weightless.

• Atomic mass can vary for elements with different numbers of neutrons, creating isotopes.