What is the amount of heat required to completely melt a 200.-gram sample of H20(s) at STP? 1.
334 J
2
836 J
3
66 800
4
452 000 J

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

How does blood clotting prevent the entry of pathogens through cuts and wounds? answer asap,, this is due tomorrow. will mark as brainliest or whatever you call it : )