How many covalent bonds can carbon, hydrogen, nitrogen, or oxygen form?

Calculate the expected ph values of the buffer systems from the experiments (a,b,c,d), using the henderson- hasselbalch equation, ph-pka+log[a-]/[ha]. use for pka values carbonic acid= 6.37, and acetic acid= 4.75.

What royal scientist used the 29th day of frozen vapor to encounter elements for mastering new culinary creations?

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 : )