Fill in the gaps for the following table of atoms.

Question

Table showing isotopes with columns for mass number, atomic number, neutrons, protons, and electrons.

Accepted Answer

So here in this practice question, it says, fill in the gaps for the following table of atoms. Before we even start, because it says the word atoms, that means we're dealing with neutral elements, and with neutral elements, that means that the number of protons equals the number of electrons. Now if we take a look here, we have our isotope name, as well the number associated with it. When we talk about our mass number, remember that is just the variable a. Atomic number is the variable z. Number of neutrons. Remember, the number of neutrons equals your mass number minus your atomic number. For protons, we can say that the number of protons equals your atomic number, or, in this case, because we're dealing with atoms, we can say the number of protons equals the number of electrons. And then finally with electrons, because we're dealing with atoms, that means that the number of protons is equal to the number of electrons. So let's start out with the first one. In the first one, we have zirconium 94. Zirconium represents the element's name, and remember the number after it would represent its mass number. So here our mass number is 94. Next, atomic number is z, but remember z is equal to the number of protons. Because we know we have 40 protons in this example, our atomic number has to be 40. And because we know the number of protons, we know the number of electrons is also 40. So So this would be the filled in row for zirconium 94. Next, we have atomic number, which is 33, and we have neutrons, which is 42. Well, let's see. We can say here that your atomic number tells us the number of protons, which is also 33. Because we're dealing with atoms, the number of protons and electrons are the same, so this would also be 33. Then we're gonna say, remember your mass number, the mass number tells us the number of protons plus neutrons together. So add up protons, add up neutrons together, that total there gives us 75. With 75, that means we're dealing with arsenic, 75. Next, we have aluminum 27. 27, of course, is the mass number. The atomic number is equal to the number of protons. The number of protons is 13, so atomic number is 13. Because we have an atom, the number of protons and electrons are the same. And then finally remember, number of neutrons equals mass number minus atomic number, so that'd be 27 minuteus 13, so that'd be 14 neutrons. And then finally we have the last row. So we have a mass number of 59. So we know the isotope element is 59. Its atomic number is 27. 27 gives us a number of protons, and because it's neutral, it also has 27 electrons. The number of neutrons, again, is equal to mass number minus atomic number, So that's gonna equal, 59 minus 27, which is 32. Then finally, we need to determine the element name. If you look on the periodic table and you find the atomic number of 27, you'd see the only element that's connected to that atomic number of 27 would have to be cobalt. So this last isotope would be cobalt 59. So just remember that our atomic view of the atom is composed of 4 parts. We have our nucleus, which houses the protons and neutrons, and then spinning around it are the electrons. Connected to these ideas are your atomic number and mass number. Knowing that we're dealing with these subatomic particles, remember the relationships they share with one another. When we're dealing with atoms, we're dealing with an equal number of protons and electrons. And remember that the mass number itself is connected to the number of protons and neutrons. Knowing and understanding these connections is a way of identifying correctly the type of isotope that you're dealing with. Now that we've taken a look at isotopes, we'll continue on to further discussions of elements of the periodic table.

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Fill in the gaps for the following table of atoms.

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Isotopes practice set