I believe the answer is 4 because solid are more compacted than liquid and gases and don't move around like liquid or gases. I'm pretty sure they have strong intermolecular forces because of how close they are. The only answer that makes sense is 4.
Answer:
You can view more details on each measurement unit: molecular weight of NaCl or grams This compound is also known as Sodium Chloride. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles NaCl, or 58.44277 grams.
Stoichiometry:
First, calculate the number of grams for one mole of Ca3 (PO3)4
(3 * (Mass of Ca)) + (4 * (Mass of P + (3 * Mass of Oxygen)))
= (3*40.08) + 4(30.97 + (3*16.00))
=(120.24) + 4(78.97)
=436.12 g / mol Ca3(PO3)4
This means there are 436.12 g per 1 mole of Ca(PO3)4. Since there are 4.50 moles of Calcium Phosphate, mulitply the molar mass of Ca(PO3)4 by 4.50 and you should get 1962.54 g. Since there are 3 sigfigs, the final answer is 1960 g.
on a side note: I put in all my work in case 1. your periodic table if different, 2. my work is wrong, 3. you put in the question wrong because I feel that the actual compound would be Ca3(PO4)3 instead of Ca3(PO3)4 (if this is the case, the answer should be 1820 g).