Final answer:
The formula for aluminum hydrogen phosphate, considering the +3 charge of aluminum and the presence of hydrogen, would be Al(H2PO4)3, using three dihydrogen phosphate ions to neutralize the charge of one aluminum ion.
Step-by-step explanation:
To determine the formula for aluminum hydrogen phosphate, we need to consider the charges of the ions involved. Aluminum ions have a charge of +3 (Al3+), while hydrogen phosphate ions (HPO42-) carry a -2 charge. However, because the question asks for aluminum hydrogen phosphate, we're likely looking at a variant of the typical aluminum phosphate, which is AlPO4.
Considering the presence of hydrogen, and referring to the provided example of calcium dihydrogen phosphate's formula (Ca(H2PO4)2), the aluminum hydrogen phosphate would likely contain the dihydrogen phosphate ion, which is H2PO41-. In this case, to balance the charge for the aluminum ion, we would need three dihydrogen phosphate ions, which means the formula of aluminum hydrogen phosphate would be Al(H2PO4)3.