How many molecules are in 2.5 mol of NaCl? (a) 1.51×10^24
(b) 146
(c) 1.51×10^23
(d) 4.15

1.51 x 10²⁴molecules

Explanation:

Given parameters:

Number of moles of NaCl  = 2.5moles

Unknown:

Number of molecules  = ?

Solution:

The number of molecules that can be found in a given mole is given as the Avogadro's constant;

       1 mole of substance  = 6.02 x 10²³ molecules

       2.5 mole of NaCl  = 2.5 x 6.02 x 10²³ molecules

                                       = 1.51 x 10²⁴molecules