Final answer:
To find the number of hydrogen atoms in ammonium phosphate, (NH4)3PO4, multiply the four hydrogen atoms in each NH4+ ion by the three ions present, resulting in a total of 12 hydrogen atoms.
Step-by-step explanation:
The question asks us to identify the number of hydrogen atoms present in the compound ammonium phosphate, which is given by the formula (NH4)3PO4. The NH4 in the formula represents the ammonium ion. There are four hydrogen atoms in each ammonium ion, NH4+ . Since the subscript outside the parentheses is 3, we have three ammonium ions in the formula. Therefore, the total number of hydrogen atoms contributed by the ammonium ions is 4 hydrogen atoms per ammonium ion times 3 ammonium ions, resulting in a total of 12 hydrogen atoms. Hence, the correct answer is A) 12.