Chemistry: chemical formula

[Rachel Maddiee]

For #14, is this 60 27Co?

[studiot]

5 hours ago, Rachel Maddiee said:

For #14, is this 60 27Co?

The atomic number of Cobalt is 27 so you have that correct. This is the number of protons.

For the question you need to know that

mass number = number of protons + number of neutrons

Which in this case is = 27 + 37 = 64

We write this as follows

[math]{}_{atomic\,no}^{mass\,no}Co[/math]

So for your particular isotope of Cobalt you should have

[math]{}_{27}^{64}Co[/math]

The istope you chose is not correct. Cobalt 60 is a common radioactive istope., but you require cobalt 64.

 

There are 28 different isotopes of Cobalt to choose from.

Quote

Isotopes of cobalt - Wikipedia

 

https://en.wikipedia.org › wiki › Isotopes_of_cobalt

Naturally occurring cobalt (₂₇Co) is composed of 1 stable isotope, ⁵⁹Co. 28 radioisotopes have been characterized with the most stable beingCo with a half-life of 5.2714 years, ⁵⁷Co with a half-life of 271.8 days, ⁵⁶Co with a half-life of 77.27 days, and ⁵⁸Co with a half-life of 70.86 days.