Prokaryotes are usually unicellular - and so would not have tissue, organs or organ systems.Some prokaryotes are multicellular, and you could potentially say that they are a tissue (many similar cells working together to perform a task). However, no prokaryotes have organs or organ systems.
The balanced equation for
Ca(OH)2 + H3PO4→ Ca3(PO4)2 + H2O is
3 Ca(OH)2 +2 H3PO4→ Ca3(Po4)2 + 6 H2O
3 moles of Ca(OH)2 reacted with 2 moles of H3PO4 to form 1 mole of Ca3(PO4)2 and 6 moles of H2O
You can have as many controls as necessary, But they must remain equal at all times in order to get the most accurate results
