[qstong0601]

write a brief experimental plan to distinguish the following pairs of substances. identify the property to be tested and include a brief explanation of the principles involved in each test.
a) He(g) and Ne(g)
b) MnCl2(s) and ZnCl2(s)
c)Zn(s) and I2(s)
d)CaCO3 and SiO2(s)

[Borek]

You just don't ask. You try, you tell us what you did, we push you in the right direction.

[qstong0601]

what i did is to test their melting points in b c d  due to their differences in structures and intermolecular forces.  but in a, since both substances are gases, i dont know how to tell them apart.

[nj_bartel]

Hint: Neon is much denser than helium.

[Arkcon]

what i did is to test their melting points in b c d  due to their differences in structures and intermolecular forces.  but in a, since both substances are gases, i dont know how to tell them apart.

They still have different melting points and boiling points.  This is an experimental plan, no one said you had to actually do it with equipment you have in the classroom lab.  So your original plan is a good one.  'Tho I do see some simpler characteristics to work with for many of them, can you find them?