Answer:
B) it is endothermic and the temperature decreased
Explanation:
Chemical reactions can be classified as endothermic and exothermic.
Endothermic reactions proceed with the absorption of heat energy (q) and have a positive value for q.
In contrast, Exothermic reactions proceed with the liberation of heat energy (q) and have a negative value for q.
It is given that the value of q = +450 J. Since q is positive, this implies that heat energy is absorbed from the surroundings resulting in a fall in temperature. Hence the reaction is endothermic.
Sr N(e⁻)=38
Sr²⁺ N(e⁻)=38-2=36
36e⁻
