The major limitation is that C) he can not definitively show what causes the difference.
It may be caused by <em>something the people are doing</em> (if so, what?) or it may be caused by <em>some environmental differences</em> or a<em> combination of both</em>.
Classify what. explain more
Answer:

Explanation:
Hello there!
In this case, by considering that the reaction between sodium hydroxide and hydrochloric acid is in a 1:1 mole ratio of these two reactants, we are able to use the following equation relating the concentration and volume of each one:

In such a way, by solving for the volume of the base, we will obtain:

Regards!
Answer: Yes,
is a strong acid.
acid =
, conjugate base =
, base =
, conjugate acid = 
Explanation:
According to the Bronsted-Lowry conjugate acid-base theory, an acid is defined as a substance which looses donates protons and thus forming conjugate base and a base is defined as a substance which accepts protons and thus forming conjugate acid.
Yes
is a strong acid as it completely dissociates in water to give
ions.

For the given chemical equation:

Here,
is loosing a proton, thus it is considered as an acid and after losing a proton, it forms
which is a conjugate base.
And,
is gaining a proton, thus it is considered as a base and after gaining a proton, it forms
which is a conjugate acid.
Thus acid =
conjugate base =
base = 
conjugate acid =
.
Answer:
a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.
Explanation:
It is given that a student performed an experiment where he dropped a nickel metal in to HCl solution. He observed the reaction and performed a splint test in the test tube that is filled with a gas which is formed while Nickle is dropped into the solution of HCl.
But the experiment that the student performed was incorrect. He must have observed the popping sound when the splint was placed in the test tube.
When the splint was added to the gas splint flared up. The hydrogen gas pops out when exposed to the flame.

Thus the correct option is (a).