They are nitrogen, oxygen, hydrogen
Answer:
156.4g K
Explanation:
I'm not sure if it is correct but I think it should be this
What do we know so far?: 2K + 1Cl2 -> 2KCl, 2 mol of Cl2
What are we looking for?: #g of K
What is the ratio of K to Cl2?: 2:1
Set up equation: 2molCl2 x 
Cancel unwanted units: 2 x 
Answer we got: 2 x 2mol K = 4mol K
Converting moles to grams: 4 x 39.1 (molar mass of K) = 156.4g K
The expected radius of a nucleus having 82 protons and 125 neutrons would be 5.2 fm.
<h3>
What is a nucleus in the atom?</h3>
The nuclei are incredibly tiny and dense. They are 10 thousand times smaller than an atom and have more than 99.9% of their mass. Protons, which have a positive charge, and neutrons, which have no electrical charge, make up the nucleus. Alternately, protons and neutrons make up an atom's nucleus. While neutrons have no charge but weigh the same as protons, protons have a positive charge that is equivalent to the orbiting electrons. Based on the 1909 Geiger-Marsden gold foil experiment, Ernest Rutherford identified the atomic nucleus in 1911, which is the compact, dense region made up of protons and neutrons at the heart of an atom.
To learn more about the nucleus, visit:
brainly.com/question/23366064
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