Question

1.5 X 1022 atoms of an element weigh about 0.9 g. The atomic mass of the element (in amu) is:
(1) 36
(2) 18
(3) 54
(4) 72
-nama number of molecules as in:​

Answer 1

the Avogadro number = 6.022×10²³

one mole of element has 6.022×10²³ atoms

the number of moles present in 1.5 × 10²² atoms= 2.5×10-²

atomic mass =given mass/number of moles

=0.9/0.025

= 36