Question

Why does the nucleus in every atom have a positive charge?

Short answer

The nucleus is positively charged because it contains protons, which are positively charged particles.

Step-by-step solution

- Identify the components of the nucleus

The nucleus of an atom is composed of protons and neutrons. Protons carry a positive charge, while neutrons have no charge (they are neutral).

- Understanding the charge of protons

Each proton in the nucleus has a positive charge of +1. For example, a hydrogen atom, which has only one proton in its nucleus, has a nuclear charge of +1.

- Neutrons and their charge

Neutrons, which are also present in the nucleus, do not contribute to the overall charge because they are neutral.

- Summing up the charges

Since the nucleus contains protons and neutrons, and neutrons do not affect the charge, the overall charge of the nucleus is determined by the number of protons, each contributing a +1 charge. Thus, the more protons in the nucleus, the greater the positive charge.

- Conclusion

The nucleus has a positive charge because it contains protons, which are positively charged particles, and neutrons, which are neutral and do not affect the overall charge.

Key concepts

Protons

The nucleus of an atom contains protons and neutrons, with protons being positively charged particles. Each proton carries a charge of +1.
This is fundamental because the number of protons defines the identity of an element. For instance, hydrogen has one proton, while helium has two.
The number of protons in the nucleus is known as the atomic number and it plays a crucial role in determining the chemical properties of the element.
Without protons, the atom wouldn't have a unique identity or positive charge. Thus, protons are essential in giving the nucleus its positive charge and defining what element the atom represents.

Neutrons

Neutrons are neutral particles found in the nucleus, which means they have no electrical charge. They have a similar mass to protons but do not contribute to the overall charge of the nucleus.

Despite their lack of charge, neutrons are crucial for the stability of the nucleus. They help to hold the nucleus together by balancing the repulsive forces between the positively charged protons.
Elements can have different numbers of neutrons, leading to different isotopes of the same element. These isotopes have the same number of protons but different numbers of neutrons, thus differing in atomic mass but not in the nuclear charge.

Nuclear Charge

Nuclear charge refers to the total charge of the nucleus, determined by the number of protons. Each proton contributes a +1 charge, meaning the nuclear charge is directly proportional to the number of protons in the nucleus.

For example, a hydrogen atom, with one proton, has a nuclear charge of +1. A carbon atom, with six protons, has a nuclear charge of +6.

The nuclear charge is important because it influences the electron configuration around the atom. Electrons are negatively charged and are attracted to the positive nuclear charge, which helps to hold them in place around the nucleus.

In summary, the positive nuclear charge is a result of the protons in the nucleus, and it determines many key properties of the atom, including its ability to attract and hold electrons.