Water, lower, and I'm not too sure for the third one... sorry.
Answer:
The protons inside an atom's nucleus help bind the nucleus together. They also attract the negatively charged electrons, and keep them in orbit around the nucleus. The number of protons in an atom's nucleus determines which chemical element it is.
Answer:
The answer is: (a) positive; (b) negative.
Explanation:
The change in enthalpy (ΔH) of a reaction is the amount of energy absorbed or released during a chemical reaction carried out at constant pressure.
a) In an endothermic chemical reaction, heat energy is absorbed by the system from the surrounding. Therefore, the sign of enthalpy change for an endothermic process is positive, ΔH= positive.
b) In an exothermic chemical reaction, heat energy is released by the system into the surrounding. Therefore, the sign of enthalpy change for an exothermic process is negative, ΔH= negative.
A Pangaea <span>is the name for continents in one landmass surrounded by gigantic ocean.
Good luck with your studies, I hope this helps!</span>
Answer:As predicted by VSEPR theory, the molecule adopts a "bent" molecular geometry similar to that of water.
Explanation: