Question

A sample is found to contain 0.500 mole of a chemical substance. a. How many atoms are present if the substance is the element Cu? 6-7 b. How many atoms are present if the substance is the element Na? c.How many molecules are present if the substance is the compound CO;? d.How many molecules are present if the substance is the compound SiF?

Answer 1

Number of atoms or molecules would be same.

use:

number of atoms = number of moles * Avogadro’s number

= 0.500 * 6.022*10^23 atoms

= 3.011*10^23 atoms

a)

3.011*10^23 atoms

b)

3.011*10^23 atoms

c)

3.011*10^23 molecules

d)

3.011*10^23 molecules