<span>I think that the effective nuclear charge increases as you go up a group and across a period.
so maybe Rh, K, Ti, Mg, P
I hope I helped :)</span>
This would be a compound because it has more than one molecules that are the same that are attached together forming a chemical bond.
Ans:
from the product / reactant solution
from the environment when no solution is involved
Endothermic reactions are those reactions that proceed with the absorption of heat energy. In this case, the enthalpy of the reactants i.e. the initial energy is lower than that of the products. Therefore, energy needs to be supplied in order to break the bonds in the reactants and allow the reaction to proceed. This energy can be absorbed either from the environment when no solution is involved or from the product reactant solution.
For example, electrolysis of water which produces H2 and O2 is an endothermic reaction. Here, energy is absorbed by water in the form of electricity (current) to split it into corresponding products.
The answer would be Chope it helps