What element can be represented by 45 #n^o#, 34 #p^+#, 34 #e^.#?

Answer 1

If there are #34# #"protons"#, the element is unquestionably #"selenium"#.

The number of protons, the number of massive, positively charged nuclear particles, is #Z,"the atomic number"#. #Z# unequivocally defines the identity of the element. For #Z=34# we have selenium.

We can be even more specific than this, because the question reported the number of neutrons, the number of neutrally charged, nuclear particles, i.e., the #""^79Se# isotope, where the #79# superscript is the isotopic mass: #"neutrons + protons"#. And thus this isotope possesses #79-34=45" neutrons"#

The problem specified #"34 electrons"#, so we know that this is a neutral element. Why?

Though I haven't done any research on it yet, I believe that this is an uncommon selenium isotope—a fission product.

By signing up, you agree to our Terms of Service and Privacy Policy

Answer 2

Axel Alvarado

The element represented by 45 electrons, 34 protons, and 34 neutrons is selenium (symbol: Se), with atomic number 34.

By signing up, you agree to our Terms of Service and Privacy Policy

Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.