Answer:82
Explanation:It’s the number in the bottom left hand corner for almost any periodic table.
The balanced reaction is: H2O2 -> H2O + (1/2) O2
However, this is a very awkward equation since it has a
coefficient in fraction form.
Another way to write this equation is:
2 H2O2 -> 2 H2O + O2
Hope this helps.
The correct option is A.
All the elements in group 1 and hydrogen has only one electron in their outermost shells, thus, they all have similar electron configuration. The elements int the periodic table are grouped in such a way that, all elements in the same group have the same number of electrons in their outermost shells. This is one of the principal reason why hydrogen is grouped with group 1 elements.<span />
Sodium bicarbonate (or baking soda) will cause both exothermic and endothermic reactions when added to water. It becomes either unstable or stable carbonic acid, which will eventually become CO2. The reaction would be exothermic is when H2CO3 (Carbonic Acid unstable) is formed and endothermic is when CO2 is.