Calculate.
(A) Mass of 1.5-gram atoms of calcium. (Atomic mass = 40)
(B) Gram atoms in 12.8 g of oxygen. (Atomic mass = 16)

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Solution

(A)
as gram atoms <=> no. of mole
Hence we have to calculate the mass of 1.5 NA of calcium

n = $\frac{g i v e n m a s s}{a t o m i c m a s s}$

mass = $n \times a t o m i c m a s s$
= 1.5 * 40
= 60 g

(B)
n = $\frac{g i v e n m a s s}{a t o m i c m a s s}$

= $\frac{12.8}{16}$ mole
= 0.8 mole

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Calculate.(A) Mass of 1.5-gram atoms of calcium. (Atomic mass = 40) (B) Gram atoms in 12.8 g of oxygen. (Atomic mass = 16)

(A)as gram atoms <=> no. of moleHence we have to calculate the mass of 1.5 NA of calcium n = givenmassatomicmassmass = n×atomicmass = 1.5 * 40 = 60 g(B)n = givenmassatomicmass = 12.816 mole = 0.8 mole

Calculate.
(A) Mass of 1.5-gram atoms of calcium. (Atomic mass = 40)
(B) Gram atoms in 12.8 g of oxygen. (Atomic mass = 16)

(A)
as gram atoms <=> no. of mole
Hence we have to calculate the mass of 1.5 NA of calcium

n = $\frac{g i v e n m a s s}{a t o m i c m a s s}$

mass = $n \times a t o m i c m a s s$
= 1.5 * 40
= 60 g

(B)
n = $\frac{g i v e n m a s s}{a t o m i c m a s s}$

= $\frac{12.8}{16}$ mole
= 0.8 mole