Answer:
The amount of Mg was enough
Explanation:
In this case, we have to start with the <u>reaction</u> between
and
, so:

If we check <u>the reaction is already balanced</u>. Now, we can do some stoichiometry to calculate the amount of Mg. The first step is the number of moles of
. To this we have to calculate the molar mass of
first, so:
Cu: 63.55 g/mol and O: 16 g/mol. So, (63.55+16)= 79.55 g/mol.
Now, we can calculate the moles:

The <u>molar ratio</u> between
and
is 1:1, so:
.
Now we can <u>calculate the mass of M</u>g if we know the atomic mass of Mg (24.305 g/mol). So:

<u>With this in mind, the student added enough Mg to recover all the Cu.</u>
Note: The HCl doesn't take a role in the reaction. The function of HCl is to dissolve the
.
I hope it helps!
<h2>Answer:</h2>
The mass of the system will remain the same if there is no conversion of mass to energy in the reaction.
<h3>Explanation:</h3>
- If the system is closed, then according to the law of mass conservation the mass of the reaction system will remain the same.
- <u><em>Law of conservation of the mass: In simple words, it is described as the mass of a closed system can never be changed, it may transfer from one form to another or change into energy.</em></u>
- But if the reaction involves energy transfer like heat or light production, in this case, the mass can be changed.
Answer:
Sodium chloride solution:
First you need to calculate the mass of salt needed (done in the explanation), which is 58.44g. Then it have to be weighted in an analytical balance in a weighting boat and then transferred into a 2L volumetric flask that is going to be filled until the mark with distilled water.
Sulfuric acid dilution:
First you need to calculate the volume needed (done in the explanation), it is 16.6 mL. Using a graduated pipette one measures this volume and transfer it into a 2L volumetric flask that is already half filled with distilled water, and then one fills it until its mark.
Explanation:
Sodium chloride solution:
Each liter of a 0.500M solution has half mol, so 2L of said solution has 1 mol of salt. Sodium chloride molar mass is 58.44g/mol, so in 2L of solution there is 58.44g of salt. That`s the mass that`s going to be weighted and transferred to a 2L volumetric flask.
Sulfuric acid dilution:
This is the equation for dilution of solutions:
Where "c1" stands for the initial concentration (stock solution concentration), "v1" for the initial volume (volume of stock solution used), "c2" for the desired concentration and "v2" for the desired volume.
When we are diluting from a stock solution we want to know how much do we have to pipette from the stock solution into our volumetric flask. We do so by isolating the "v1" term from the dilution equation:
in this case that would be:
Capsaicin is the chemical in the peppers, and then milk reverses it by using casein (A fat loving compound) to bond to the capsaicin and wash it away. Hope this helps!