Answer:
Explanation:
When we react Hydrochlorid Acid with zinc we have the following reaction:
2HCl(aq) + Zn(s) --> ZnCl2(aq) + H2(g)
The hydrogen gas formed is lost to the environment, so we can affirme that in the start we have the mass for all the H, Cl and Zn atoms in the solution, but after the reaction occurs, we have only the mass for the Cl and Zn atoms.
That's why the mass is less than the original.
The law that the student was told is only applied to closed environments.
Each orbital must contain a single electron before any orbital contains two electrons.
Answer:

Explanation:
Hello,
In this case, given that a typical aspirin tablet contains 5.00 grains of pure aspirin, the first step here is to compute the mass of those grans per tablet given that 1.00 g = 15.4 grains:

In such a way, the number of aspirin tablets are computed considering the total mass of aspirin and the mass per tablet:

Best regards.
159.3 g
mol= mass (g)/ molecular weight (g/mol)