Question

what are the total number of moles of atom in 4.32g of Sc(NO3)3.
plzzzz answer​

Answer 1

Answer : The total number of moles of atom in 4.32 g of $Sc(NO_3)_3$ are 0.0187 mole.

Explanation : Given,

Mass of $Sc(NO_3)_3$ = 4.32 g

Molar mass of $Sc(NO_3)_3$ = 230.97 g/mole

Formula used :

$\text{Moles of }Sc(NO_3)_3=\frac{\text{Mass of }Sc(NO_3)_3}{\text{Molar mass of }Sc(NO_3)_3}$

Now put all the given values in this formula, we get:

$\text{Moles of }Sc(NO_3)_3=\frac{4.32g}{230.97g/mole}=0.0187mole$

Therefore, the total number of moles of atom in 4.32 g of $Sc(NO_3)_3$ are 0.0187 mole.

Answer 2

we have to find out the total number of moles of atom in 4.32g of Sc(NO3)3

we know, atomic mass of Sc = 45 g/mol

atomic mass of N = 14 g/mol

atomic mass of O = 16 g/mol

now, molecular mass of Sc(NO3)3 = 45 + 3 × (14 + 3 × 16)

= 45 + 3 ( 14 + 48)

= 45 + 3 × 62

= 45 + 186

= 231 g/mol

now, no of moles of Sc(NO3)3 = weight of Sc(NO3)3/molecular weight of Sc(NO3)3

= 4.32/231 = 2/100 = 0.02 mol

• so, no of moles of Sc = 0.02 mol
• no of moles of N = 3 × 0.02 = 0.06 mol
• no of moles of O = 3 × 3 × 0.02 = 0.18 mol