Question

Thallium consists of about 30% Th-203 and 71% Th-205. The relative mass will be closest to what value?
Question 5 options:

A)

201

B)

202

C)

203

D)

204

Answer 1

@BioHazard9064
@arronq

Answer 2

This involves some simple math.

The molar mass of an element (as listed on the periodic table) accounts for all the isotopes of that element in a weighted average according to their abundance in nature.

\(\sf Molar~mass=\sum(abundance~~\%*m_{isotope~i})\)

\(\sf Molar ~mass_{Th}=0.3*m_{Th-203} + 0.71*m_{Th-205} \)

Answer 3

ummm okay

Answer 4

So all you do is multiply the abundance of each isotope by it's respective mass then add these values together.

Answer 5

The mass is indicated after the dash. For example, the mass of Th-203 is 203 lol

Answer 6

so D?

Answer 7

sounds right

Answer 8

thanks

Answer 9

no probs

Answer 10

i got a couple more questions are you busy?

Answer 11

nope, post them

Answer 12

okay thank you