Calculate the standard enthalpy of formation of liquid water at 75°C.

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

they are both synthetic elements

explanation:

d

thats a little if u want the answer just look it up on google thats what i do haha : )