Answer:
The answer you are looking for is A
The answer should be A, flammability.
The isotopes of the same element would result in the same chemical properties, as the number of protons and electrons are not changed, meanwhile, the physical properties would be slightly different with each other because they have different numbers of electrons.
Out of the 4 options, only option A is a chemical property. Chemical properties are the properties of an element reacting with other substances that creates new substances at the end. While physical properties are the ones that does not produces new substances or any reactions. They are usually observable and measurable.
Therefore, since flammability is a chemical property, the answer is A.
Explanation:
In a voltaic cell, oxidation reaction occurs at anode whereas reduction reaction occurs at the cathode.
Hence, the half-cell reaction taking place at anode and cathode will be as follows.
At anode (Oxidation) :
...... (1)
At cathode (Reduction) : 
So, in order to balance the half cell reactions, we multiply reduction reaction by 3. Hence, reduction reaction equation will be as follows.
........ (2)
Therefore, overall reaction will be sum of equations as (1) + (2). Thus, net reaction equation is as follows.
The pressure will continue to build up eventually causing a release of pressure or an explosion.