Why does a 100 gram piece of wood float but a 100 gram piece of metal sink

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 : )

Find the mass, in grams, of 5.00*10^23 molecules of f2

I’m an electrically neutral atomic any element, there are equal numbers of