There are 9.8 moles of sodium (Na) in a sample of 5.87 x 10²⁴ atoms of sodium.
<h3>HOW TO CALCULATE NUMBER OF MOLES?</h3>
The number of moles of a substance can be calculated by dividing the number of molecules in the substance by Avogadro's number. That is;
no. of moles = no. of atoms ÷ 6.02 × 10²³
According to this question, there are 5.87 x 10²⁴ atoms of sodium. The number of moles is as follows:
no. of moles = 5.87 x 10²⁴ atoms ÷ 6.02 × 10²³
no. of moles = 0.98 × 10¹
no. of moles = 9.8moles
Therefore, there are 9.8 moles of sodium (Na) in a sample of 5.87 x 10²⁴ atoms of sodium.
Learn more about no. of moles at: brainly.com/question/14919968
When Lead (II) acetate and Hydrogen sulfide react, they form Lead sulfide and Acetic acid. The reaction is a reduction-oxidation (redox) reaction.
The balanced chemical reaction is this:
Pb(C2H3O2)2 + H2S --> PbS + 2C2H4O2
And the net ionic reaction is this:
Pb2+ + S2- --> PbS
:
Option (c) is the correct answer.
Explanation:
It is known that when we move down a group then there is increase in size of atom. This is because there occurs increase in number of shells in the atom.
Also, when an atom loses electrons then it acquires a positive charge and size of the atom decreases. On the other hand, when an atom gain electrons then it acquires a negative charge and size of the atom increases.
Since, both Rb and K are same group elements and Rb has larger atomic size than K.
Hence, we can conclude that out of the given options K^{+}
+ has the smallest size.