How many protons and neutrons does a nucleus designated as 40 18 X contain?

Everyone in this example, we need to identify the symbol number of protons and number of neutrons for the isotope 100 x. So recall that for isotope symbol. The 100 here represents our mass number X. Is supposed to be our atom, which is what we need to identify for our answer. And then the 44 here represents our atomic number. Sorry about that. So we should recall that our mass number is found by taking our number of protons and adding that to our number of neutrons. And we should recall that atomic number represented by the symbol Z is going to equal our number of protons and it's also going to equal our number of electrons for neutral atoms only. So because we're already given the atomic number as 44, we can say Z Equals 44 because it's given to us in our symbol. And so we can look to our parodic tables and say that therefore the atomic number 44 would correspond to the atom ruth any. Um, are you on our periodic tables? So we can say therefore, are you is X. To replace that in our symbol are isotopes symbol. Our next step is to confirm our number of protons and neutrons. So we need to first find protons in order to find neutrons. Now because we have been given our atomic number being 44 in our symbol, we can say also. Therefore, since the atomic number is equal to 44, we have 44 protons in ruth any. um and since it is a neutral isotope, We don't have a charge here in our given symbol. So we can say and we have 44 electrons. So what we've determined so far is the identity of X. So we have 100 ruth Anne. Um as our isotope, it has the atomic number 44, which was already given to us. And we've confirmed that we have 44 protons so far. So now to find our number of neutrons, as we've outlined above, protons added two neutrons gives us our mass number and our mass number given to us in the prompt is 100 here. So what we can do is take our mass number and number of protons to find our number of neutrons. So we would say that our number of neutrons Is found by taking our mass number given to us in the prompt as 100 And subtracting that from our number of protons, which we determined from our given atomic number in our symbol being 44. So 100 -40 for protons. So, this difference gives us our number of neutrons equal to a value of 56. So for our final answers to complete this example, we've identified our proper symbol for this isotope here. We've sorry, we've also identified our number of neutrons and we've also identified our number of protons. So everything boxed in blue represents our final answer to complete this example, I hope that everything I reviewed was clear if you have any questions. Just leave them down below and I'll see everyone in the next practice video.