Answer:
the second one is the answer
Cheese bc cheese is good and it’s a tool
Answer:
Explanation: Mendeleev arranged the elements on the basis of their atomic mass. Melting and boiling point were used as the physical characteristics in deciding the position of elements. He arranged the elements and wrote the formula of their oxides and hydrides which seemed to possess same chemical formula.
Explanation:
Correct Answer: C<span>a(s) + 2H2O(ℓ) → Ca(OH)2(aq) + H2(g)
Reason:
A reaction (</span>transmutation) is said to be spontaneous if it occurs on it's own, without any external stimulus. For spontaneous reaction, change in free energy (ΔG) is negative.
Among the given reactions, Ca(s) + 2H2O(ℓ) → Ca(OH)2(aq) + H2(g) occurs on its own with supplying external energy. Hence, it is a spontaneous reaction. Further, it is an exothermic reaction. So during the reaction heat is given out by the system.
On other hand, reaction: <span>2KClO3(s) → 2KCl(s) + 3O2(g) is a decompostion reaction. For occurrence of reaction, heat has to be supplied to system. Hence, this reaction is non-spontaneous in nature. </span>
