Well the group fluorine is in is known as Halogens. Halogens all have seven valence electrons in their outer shell. They exist as diatomic molecules. Furthermore they readily combine with metals to form salts
Student B because it requires a hypothesis
Number of moles = 8.3 x 10⁻¹³
<h3>Further explanation
</h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
5 x 10¹¹ atoms of Silver :

Explanation:
1) their is no formation of new substance
2) the reaction can be reverse i.e if we heat sugar solution it we give us sugar and water.