How many atoms of boron are in 3.66 moles of boron?

The number of atoms = 2.20×10^24

Explanation:

From stoichiometry relations;

Mole =

Number of particles/ Avogadro's constanst

Particles may be atoms, molecules or ions

Avogadro's constant is the number of atoms in a mole = 6.02×10^23

3.66= Number of atoms /6.02×10^23

Number of atoms =3.66×6.02×10^23

Number of atoms =2.20×10^24

Therefore the number of atoms present is

2.20×10^24

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6