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1 vote
The total number of atoms represented by the formula Fe3(PO4)2 is

A. 11
B. 12
C. 13
D. 15

User KingPin
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2 Answers

5 votes
C is the answer 3 + 2 +8 = 13
User Ntalbs
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2 votes

Answer:

C.

Step-by-step explanation:

We have to keep in mind for this question that we have to take into account the subscripts.


Fe_3(PO_4)_2

The subscript will affect only the number in the left, so the first part would be:


Fe_3

In this part we will have 3 iron atoms. Then we will have:


(PO_4)_2

In the
PO_4 we will have 1 atom of P and 4 atoms of O. (When we dont have any number as subscript we have to assume that we have a "1")

Then we have a "2" out side the the parenthesis
(PO_4)_2, so we have to multiply by "2" all the atoms inside the parenthesis, so:

1 atom of P x 2 = 2

4 atoms of O x 2 = 8

So, in total we will have:

3 atoms of Fe + 8 atoms of O + 2 atoms of P = 13 atoms

User Sleeplessnerd
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