Answer:
5.9x10²² atoms of Cu are in one naira coin
Explanation:
To solve this question we need to find the mass of Copper. Then, using its molar mass (Cu = 63.546g/mol) we must find the moles of Cu and its atoms using Avogadro's number:
<em>Mass Cu:</em>
7.3g * 86% = 6.278g is the mass of Cu.
<em>Moles Cu:</em>
6.278g * (1mol / 63.546g) = 0.099moles Cu
<em>Atoms Cu:</em>
0.099moles Cu * (6.022x10²³atoms / 1mol) =
<h3>5.9x10²² atoms of Cu are in one naira coin</h3>
Answer:

Explanation:
Hello,
In this case, given the acid, we can suppose a simple dissociation as:

Which occurs in aqueous phase, therefore, the law of mass action is written by:
![Ka=\frac{[H^+][A^-]}{[HA]}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH%5E%2B%5D%5BA%5E-%5D%7D%7B%5BHA%5D%7D)
That in terms of the change
due to the reaction's extent we can write:

But we prefer to compute the Kb due to its exceptional weakness:

Next, the acid dissociation in the presence of the base we have:
![Kb=\frac{[OH^-][HA]}{[A^-]}=1x10^{6}=\frac{x*x}{0.1-x}](https://tex.z-dn.net/?f=Kb%3D%5Cfrac%7B%5BOH%5E-%5D%5BHA%5D%7D%7B%5BA%5E-%5D%7D%3D1x10%5E%7B6%7D%3D%5Cfrac%7Bx%2Ax%7D%7B0.1-x%7D)
Whose solution is
which equals the concentration of hydroxyl in the solution, thus we compute the pOH:
![pOH=-log([OH^-])=-log(0.0999)=1](https://tex.z-dn.net/?f=pOH%3D-log%28%5BOH%5E-%5D%29%3D-log%280.0999%29%3D1)
Finally, since the maximum scale is 14, we can compute the pH by knowing the pOH:

Regards.
<span>
It contains 6.02 mc001-1.jpg 1023 grams of sodium chloride.
It is the mass of 12 carbon atoms.
It contains 6.02 mc001-2.jpg 1023 particles of a given substance.</span>
Answer:
0.51M
Explanation:
Given parameters:
Initial volume of NaBr = 340mL
Initial molarity = 1.5M
Final volume = 1000mL
Unknown:
Final molarity = ?
Solution;
This is a dilution problem whereas the concentration of a compound changes from one to another.
In this kind of problem, we must establish that the number of moles still remains the same.
number of moles initially before diluting = number of moles after dilution
Number of moles = Molarity x volume
Let us find the number of moles;
Number of moles = initial volume x initial molarity
Convert mL to dm³;
1000mL = 1dm³
340mL gives
= 0.34dm³
Number of moles = initial volume x initial molarity = 0.34 x 1.5 = 0.51moles
Now to find the new molarity/concentration;
Final molarity =
=
= 0.51M
We can see a massive drop in molarity this is due to dilution of the initial concentration.
Answer: choice B
Explanation: Heat flows from high to low. After you convert the Celsius into kelvin the Zn pellet has 323K and the water has 301K which results the transfer of the heat energy of the pallet to the water. ( you don’t have to convert, but it just make it easier) hope this helped you :)