Hey there,
Your answer would be
Coefficients are placed in front of the reactants and/or products
Hope this helps,
<h2>- <em>Mr. Helpful</em></h2>
D. Kinda simple, don’t think much explaining is needed.
The percent composition by mass of an element is determined by dividing the molar mass of the element by the molar mass of the compound. In this case, the molar mass of magnesium is 24. Hence the answer to this problem is A. 24/184 x 100
Since the forward reaction is endothermic (heat is consumed in the reaction) that means that the enthalpy change for the forward reaction is a positive value.
Therefore, i would say that the reverse or backward reaction is exothermic (heat is released in the reaction to the sorroundings) and that the enthalpy change is a negative value.
