How many protons, neutrons, and electrons are in the following atoms? (a) ⁸⁴Kr (b) ²⁰⁰Hg (c) ⁷⁰Ga

Verified step by step guidance

1. Identify the atomic number of gallium (Ga) from the periodic table, which is 31. This tells us the number of protons in the atom.
2. Since the atom is neutral, the number of electrons is equal to the number of protons. Therefore, gallium has 31 electrons.
3. The mass number of the isotope is given as 70. The mass number is the sum of protons and neutrons in the nucleus.
4. Calculate the number of neutrons by subtracting the number of protons from the mass number: Neutrons = Mass number - Protons = 70 - 31.
5. Summarize the findings: Gallium-70 has 31 protons, 31 electrons, and the calculated number of neutrons.

Key Concepts

Atomic Structure

Atoms consist of three primary subatomic particles: protons, neutrons, and electrons. Protons are positively charged and reside in the nucleus, while neutrons are neutral particles also found in the nucleus. Electrons are negatively charged and orbit the nucleus in electron shells. The number of protons defines the element, while the number of neutrons can vary, resulting in different isotopes.

Isotopes

Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons. For example, gallium-70 (70Ga) has 31 protons (as gallium's atomic number is 31) and 39 neutrons (70 - 31 = 39). Understanding isotopes is crucial for determining the atomic mass and stability of an element.

Charge Balance

In a neutral atom, the number of electrons equals the number of protons, balancing the overall charge. For gallium-70, with 31 protons, there are also 31 electrons, ensuring the atom is electrically neutral. This concept is fundamental in understanding atomic behavior and chemical bonding.