Answer:
Atoms consist of three basic particles: protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).
Explanation:
The given data is as follows.
Current (I) = 3.50 amp, Mass deposited = 100.0 g
Molar mass of Cr = 52 g
It is known that 1 faraday of electricity will deposit 1 mole of chromium. As 1 faraday means 96500 C and 1 mole of Cr means 52 g.
Therefore, 100 g of Cr will be deposited by "z" grams of electricity.

z = 
= 185576.9 C
As we know that, Q = I × t
Hence, putting the given values into the above equation as follows.
Q = I × t
185576.9 C =
t = 53021.9 sec
Thus, we can conclude that 100 g of Cr will be deposited in 53021.9 sec.
1.51 x 10²⁵atoms
Explanation:
Given parameters:
Mass of Na = 578g
Unknown:
Number of atoms = ?
Solution:
To find the number of atoms, we must first find the number of moles the given mass contains.
Number of moles = 
molar mass of Na = 23g
Number of moles =
= 25.13moles
1 mole of a substance = 6.02 x 10²³atoms
25.13 mole of Na = 25.13 x 6.02 x 10²³atoms
This gives 1.51 x 10²⁵atoms of Na
Learn more:
Avogadro's constant brainly.com/question/2746374
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