It’s c I believe because it says 209 years to complete an orbit so hint yourself ?.....
when iron and oxygen the reactin form Fe2O3 balance equation for this is <span>4Fe + 3O2---> 2Fe2O3
9moles of O2 are needed to produce 6mol of Fe2O3 since the ratio of oxygen to iron(II)oxide is 3:2
hope its help</span>
The correct answer is b, 18 protons
Explanation:
As per the Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
Hence, according to this law the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
..........(1)
..............(2)
The final reaction is as follows:
.............(3)
Therefore, adding (1) and (2) we get the final equation (3) and value of
at 298 K will be as follows.
=
+
= -314 kJ + (-80) kJ
= -394 kJ
Thus, we can conclude that
at 298 K for the given process is -394 kJ.
<span>i believe its water has a high temperature. hope i helped</span>