What would you do to a question like this one?

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What is the atomic number and the number of neutrons?

2 Answers
Mar 14, 2018

You simply DON'T KNOW here...

Explanation:

The mass number of an atom is to a first APPROXIMATION the SUM of the massive nucular particles, protons, and neutrons. Now it is a fact that #""^7Li# has three positively charged nuclear particles, i.e. #Z=3#, and MOST isotopes of lithium contain 4 neutrons....#3+4=7#...and so the mass of this isotope is #7*g*mol^-1#.

The question is admittedly poor...and requires better specification.

Mar 14, 2018

enter image source here mass number is show in the pic

Explanation:

1- Mass number is always the larger number
2- Atomic number is the small one

so if mass number is 7 go to the periodic table and search for number 7 is you find it make sure its the larger number of the element

the answer is :
mass number is : 7
this element is Li (lithium)
so the Atomic number is 3
neutron = mass no. - atomic no.
neutron = 7-3 = 4

Atomic number equal to the number of P+ and equal to the number of e-
- note : remember atomic number is the small one.
- atomic number = proton = electron

to find neutron subtract mass number from atomic number to find the neutron :
remember this formula to find the neutron :
neutron = mass number - atomic number

if you have any question feel free to ask me

and hope you understand,
Amna.