A nuclide contains 30 positively-charged particles, and 40 neutrally-charged massive particles. What is the nuclide?

1 Answer
Sep 6, 2016

Answer:

Given a neutral atom we have #""^70Zn#.

Explanation:

If it is a neutral atom (and we must assume so), for every electron there must be a positively charged nuclear proton. Thus #Z," the atomic number = 30"#. And thus the element is zinc metal, #Zn#, because this is how zinc is identified.

The mass number is simply the sum of nuclear protons and neutrons: #30+40=70#. Now this is a fairly rare isotope of #Zn#, maybe less that 1% abundance. The most probable zinc isotope is #""^64Zn#. How many (i) electrons, and (ii) neutrons, does this isotope have?