Question

calculate no of moles in 5.75g of sodium​

Answer 1

no of moles = given mass (m) / actual mass (M)

Sodium actual mass= 23g

given mass= 5.75

no. of moles = 5.75/23

                     =0.25 moles

Answer 2

Answer- Concept to be used:

No of moles(n)= Given mass(m)/ Molar

Mass (M)

According to the question,

Given element: Sodium (Na)

Given mass (m)= 5.75 g

Molar Mass(M)= 1[Na]

= 1[23] (Atomic mass of Na= 23 u)

= 23 g

n= m/M

n= 5.75/23

n= 0.25 moles

Hence, no. of moles in 5.75 g of Sodium is 0.25 moles.