Answer:
no of atoms = 13.9 x 10^25
Explanation:
No. of moles = mass of compound / molar mass of compound
As ; mass of sodium = 5.3 x 10^3 g
Molar mass of sodium = 22.9 g/ mol
putting values
n = 5.3 x 10^3 / 22.9
n = 231.4 mol
Also; no of mol (n) = no of particles / Avagadros number
so no of particles = n x Avagadros no.
put n = 231.4 and Avagadros no = 6.023 x 10^23
no of particles = 231.4 x 6.023 x 10^23
= 13.9 x 10^25
Answer:

Explanation:
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In this case, since the precipitation of the lead iodide is related to the iodide ion in solution, if we make react lead (II) nitrate with an iodide-containing salt, a possible chemical reaction would be:

In such a way, since 15.71 mL of a 0.5770-M solution of lead (II) nitrate precipitates out lead (II) iodide, we can first compute the moles of lead (II) nitrate in the solution:

Next, since there is a 1:2 mole ratio between lead (II) nitrate and iodide ions, we compute the moles of those ions:

Finally, since the mixing of the two solutions produce a final volume of 40.71 mL (0.04071 L), the resulting concentration (molarity) of the iodide ions in the student's unknown turns out:

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You first weigh you're solid to determine it's mass. Then put it in a container that has liquid with definite volume which can't dissolve solid, absolutely when you put solid in liquid, liquid raise and you have volume of solid.
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specificmass=mass/volume</span></span>