A synthesis yielded 222g of phosphoric acid. How many moles of phosphoric acid were produced?

I keep dividing 222g/98g (molar mass) which gives me 2.265. Every time I put the answer in, it tells me I am wrong.

You are right that mols = grams/molar mass.

I think your problem, often the problem with on-line values from a data base, is that you have reported an answer with too many significant figures.
222/98.0 = a max of 3 places. You have reported 4. Round that to 2.26 (or 2.27 depending upon how your instructor has told you to round with a terminal 5)

To calculate the number of moles of a substance, you need to use the formula:

moles = mass / molar mass

In this case, you correctly used the molar mass of phosphoric acid, which is 98 g/mol. However, it seems there might be an error in your calculation. Let's go through it step by step:

mass of phosphoric acid = 222 g
molar mass of phosphoric acid = 98 g/mol

Now let's substitute these values into the formula:

moles = 222 g / 98 g/mol

Dividing 222 g by 98 g/mol, we get:

moles = 2.265 moles

Based on your explanation, it seems that you have correctly solved the problem. However, if the answer is being marked as incorrect, there might be a formatting issue or a specific acceptable format for answers that you need to consider.

Make sure you are using the correct units and rounding to the appropriate number of decimal places. Additionally, check if the system requires you to enter the answer as a whole number or in a specific format (e.g., scientific notation).