Answer:
a. Due to the evolved hydrogen from potassium to water reaction being able to reach the flash point of the reaction temperature
b. Non-metal
The molecular formula is N₂O₃
Step-by-step explanation:
a. The heat of the reaction between calcium and water is given as follows
Ca + 2 H₂O → H₂ + Ca(OH)₂ ΔH = -431.15 kJ which is exothermic, Entropy = -125.29 J/K
The heat of the reaction between potassium and water is given as follows
2 k + 2 H₂O → 2 KOH + H₂ ΔH = -393.15 kJ Entropy = 44.91 J/K
Therefore, the reaction between potassium and water occurs more vigorously than the reaction between calcium and water such that the flash point for the released hydrogen gas is reached in the case of potassium
b. The acidic oxides are oxides of metals or non-metals that react with water to produce an acid
Given the valence of the oxide which is +3, the oxide can be aluminium, Al or nitrogen, N, however, Al₂O₃ behaves both as an acid and a base, therefore, the likely candidate is nitrogen, which shows that X is a non-metal
The molecular formula is therefore;
N₂O₃