Question

What would the isotope symbol (in hyphen notation) look like for an atom that has a mass number of 204 and an atomic number of 82?

O a
Lead-82
ob
Thallium-204
Ос
Lead-204
Thallium-82
Od
HELP ASAP

Answer 1

`\boxed {\boxed {\sf C. \ Lead-204}}`

Step-by-step explanation:

One way of writing an isotope is hyphen notation or:

• element name - mass number

We know the mass number (protons and neutrons) is 204. We can automatically eliminate choices A and C, because they claim the mass number is 82.

Now we must find the element name. We know the atomic number or number of protons is 82. Look on the periodic table for the element with atomic number 82, which is lead.

Therefore,

• element name = Lead
• mass number = 204

The isotope notation in hyphen notation is: Lead-204