1.70 × 10³ seconds
<h3>Explanation </h3>
+ 2 e⁻ → 
It takes two moles of electrons to reduce one mole of cobalt (II) ions and deposit one mole of cobalt.
Cobalt has an atomic mass of 58.933 g/mol. 0.500 grams of Co contains 
of Co atoms. It would take 
of electrons to reduce cobalt (II) ions and produce the 
of cobalt atoms.
Refer to the Faraday's constant, each mole of electrons has a charge of around 96 485 columbs. The 0.01697 mol of electrons will have a charge of 
. A current of 0.961 A delivers 0.961 C of charge in one single second. It will take 
to transfer all these charge and deposit 0.500 g of Co.
<u>Moseley</u> discovered that <u>elements</u> with similar properties occurred at <u>regular intervals</u> when the elements were arranged in order of increasing
<u>"</u><u> </u><u>Atomic number </u><u>"</u>
1 mol of any substance is made of 6.022 x 10²³ units, these units could be atoms making up elements or molecules making up a compound.
In this case. 1 mol of Li is made of 6.022 x 10²³ atoms of Li
The molar mass of Li is 6.94 g/mol
Therefore mass of 1 mol of Li is 6.94 g
In 6.94 g of Li there are - 6.022 x 10²³ atoms
Then in 766.3 g of Li there are - 6.022 x 10²³ atoms / 6.94 g x 766.3 g = 665 x 10²³
There are 6.65 x 10^25 atoms of Li
