If you know only the following information can you always determine what the element is? (Yes/No).a. Number of protons (yes or no) b. Number of...

The key to this is first to understand that in a neutral
atom, the number of positive protons and negative electrons is always equal. Secondly,
the  number of protons is always the atomic number of the element and uniquely
identifies the element.

because of the existance of
isotopes for all elements, the number of neutrons will vary and cannot be used by itself
to determine the identity of the element.

That being said,
for a) the proton # identifies the element.

for b) neutrons
do not identify the element

for c) since it is neutral the
# of electrons = # of protons = atomic number = identity of the
element.

for d) since it does not specify if the substance
is neutral or not, the number of electrons cannot be used to identify the element. It
could be a cation or anion vs. a neutral ion, and could have a charge of anywhere from
+1 to +4 to -1 to -3.