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!
Answer:

Explanation:
First reaction gives you the number of moles or the mass from Carbon and hydrogen
for carbon:


Analogously for hydrogen:
0.0310g
have 0.0034gH or 0.0034mol of H
In the second reaction you can obtain the amount of nitrogen as a percentage and find the mass of N in the first sample.

now

this is equivalet to 0.002mol of N
with this information you can find the mass of oxygen by matter conservation.

this is equivalent to 0.004molO
finally you divide all moles obtained between the smaller number of mole (this is mol of H)

and you can multiply by 5 to obtain: 
<span>When one talks about ppm in a liquid solution someone means mg/L so we would not be using the density. This usually means ug/g or mg/kg
0.115 g Na^+ * 10^6 ug/1 g = 115000 ug/g
4.55 L * 1000 mL/1L = 4550 mL
Concentration of Na^+ in ppm:
115000 ug/g /4550 mL = 25.27 pm of sodium ion</span>
Answer:
Explanation:Here's li
nkly/3fcEdSx to the answer:
bit.
Answer:
Ammonia (NH3)
Explanation:
its an ionic compound where N nitrogen is bonded to covalent molecules