Question

5. Calculate the mass of the following substances
a) 25 x 1023 molecules of N2

Answer 1

Answer:

0.028kg

Explanation:

We were given 2.6 × 1023 molecules of SO 2 That means that

N = 2.6 × 1023 molecules

Use

n (number of moles) = N

                                     NA (Avogadro's constant)

to get

n =2.6×1023 molecules

   6.02 ×1023 molecules/mol  = 0.432 moles

Now use

m = n × M (molar mass)

to get

m = 0.432 mol × 64.066 g/mol = 27.677 g

So

m (in kilograms) = 27.677 g

                          103 g/kg       = 0.028 kg

Answer 2

Answer:

28 g

Explanation:

In addition, to what ellewhite 1864 wrote, 0.028/1000=28g