The first 92 elements of the periodic table are naturally occurring elements.
Answer: Sodium also floats on the surface, but enough heat is given off to melt the sodium (sodium has a lower melting point than lithium and the reaction produces heat faster) and it melts almost at once to form a small silvery ball that dashes around the surface.
Explanation:
Answer:
A. endothermic.
A. Yes, absorbed.
Explanation:
Let's consider the following thermochemical equation.
2 HgO(s) ⇒ 2 Hg(l) + O₂(g) ΔH = 182 kJ
The enthalpy of the reaction is positive (ΔH > 0), which means that the reaction is endothermic.
182 kJ are absorbed when 2 moles of HgO react (molar mass 216.59 g/mol). The heat absorbed when 72.8 g of HgO react is:

For the very last question you would first divide 8,900 by 12 and the number you get will be the answer. You should get 741.66
I think it is C, because a covalent bond is a distribution of 2 atoms to 1 electron, meaning they are sharing and not exchanging, and the electronegravity would be above 1.7