9.87X1024 atoms (NH4)3 PO4= how many moles

16.4moles

Explanation:

From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 atoms.

This clearly indicates that 1mole of (NH4)3PO4 also contains 6.02x10^23 atoms.

Now, if 1mole of (NH4)3PO4 contains 6.02x10^23 atoms,

Then Xmol of (NH4)3PO4 will contain 9.87X10^24 atoms i.e

Xmol of (NH4)3PO4 = 9.87X10^24/6.02x10^23 = 16.4moles

sorry i was late, but i don't know what assignment your talking about, i'm in flvs as well, im in earth space science. but u are behind pace bc every class should be in the 3's or 4'