What are the number of protons, neutrons, and electrons in the following isotopes? a. 38^89 Sr

What are the number of protons, neutrons, and electrons in...

Key Concepts

Isotope

An isotope refers to different forms of the same element, which all have the same number of protons but vary in the number of neutrons. This variation in neutron count results in different mass numbers while maintaining chemical identity, which is crucial in the study of nuclear chemistry and physics.

Neutron Calculation

The process of determining the number of neutrons in an atom involves subtracting the atomic number (the number of protons) from the mass number (the total number of protons and neutrons). This calculation is key for understanding the differences between various isotopes of an element.

Atomic Number

The atomic number is the number of protons in the nucleus of an atom. It uniquely identifies the element and is used to determine various elemental properties. In problems, the atomic number is often provided as the subscript in isotopic notation, and for neutral atoms, the number of electrons equals the atomic number.

Mass Number

The mass number is the sum of protons and neutrons in an atom’s nucleus. It is typically written as a superscript to the left of the element symbol in isotopic notation. The mass number is essential for calculating the number of neutrons in an isotope by subtracting the atomic number from it.

Transcript

00:01 All right, we have several different atoms or elements that we're going to be trying to find the proton, neutron, and electron count of.

00:16 Finding the number of protons is easy because every element is assigned a proton number, and that is always going to be the same no matter what.

00:26 And then for electrons, they're actually the same as the number of protons.

00:33 And then the neutrons can be a little bit different based on its mass because there can be isotopes.

00:40 Okay, so let's look at strontium right here.

00:42 It's sr.

00:44 So what is the proton number? you can actually find that from its atomic number right here, which is 38.

00:49 So strontium has 38 protons.

00:55 And then electrons are going to be exactly the same.

01:00 So it'll have 38 electrons as well.

01:05 And then let's look at the neutrons.

01:06 How do we find that we take the math number, which is in the top left corner, and subtract the number of protons it has, which is 38? so if we do that in the calculator, it'll be 89 minus 38, which we're left with 51.

01:22 So this strontium atom has 51 neutrons.

01:29 Okay, and we'll move on to the next one, do the same thing.

01:32 So here we have chromium.

01:34 If we look at the bottom left, it'll give us the atomic number, which is 24.

01:38 That's the same number that's on the periodic table as well.

01:42 So we have 24 protons.

01:48 And electrons, again, it's going to be the same.

01:51 So we'll have 24 electrons...