1 mol of Silicon = 28.0855 g (in average)
then
1 mol = 6.022*10^23 atoms
then
28.0855/(6.022*10^23) g/atom
4.66381*10^-23 g per atom
A mixture is a portion of matter made up of two or more substances called constituents. Mixtures are the product of the mechanical joining of substances without change in chemical nature, and therefore, each constituent retains its properties.
the option 4
It is considered to be a conductor
name= calcium
atomic mass= 40.078 atomic mass unit
no of protons= 20
no of electrons=20