Answer: The age of the tool is 15539 years
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = 100
a - x = amount left after decay process =
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.

b) for 15.5 % of original amount

Thus age of the tool is 15539 years
<span>The ends of a bar magnet are called POLES</span>
Answer:
Lewis acid- Fe3+
Lewis base- water molecule
Explanation:
Acids and bases have been defined in diverse ways. There have been definitions put forward by Arrhenius, Brownstead and Lowry as well as Lewis. Each definition his useful in its own way.
Lewis acids are lone pair acceptors such as metal ions. This implies that in the particular instance of this reaction, Fe3+ is the lewis acid.
Similarly, a Lewis base is a lone pair donor, all ligands are lone pair donors since they donate one or more lone pairs of electrons to Lewis acids. In the particular instance of this reaction, the Lewis base is the water molecule.