Answer:
How is it possible that helium, having 2 protons, and lithium, having 3 protons, are so different in terms of their physical properties? How come one is a gas at room temperature and the other is a solid metal?
Then why lithium and beryllium, the latter having 1 proton more than the former, are both metals and solids at room temperature?
Now if you remove neutrons from the nuclei of any element (except hydrogen), they form isotopes that have similar chemical properties and different physical properties, while still being an atom of the same element - therefore the protons, if I understand it correctly, are what determine whether an element is a gas or a solid at room temperature, and not the neutrons (or even electrons). Is this true?
The deeper question is that why do the properties of elements and their atoms change significantly - in some cases as with helium and lithium - just by having an additional proton in their nucleus, if the fundamental building blocks of protons (quarks) are identical for each proton? Then in the case of lithium and beryllium, why is the change in physical properties so subtle compared to the first case?
Edit
This question has already been asked before, however I am specifically interested in helium and lithium - why is one a gas and the other a solid metal at room temperature, having completely different chemical and physical properties? Is this a result of the electron shell configuration? Why does an extra proton, neutron and electron give rise to such a difference?
Answer:
77.473675 grams of sodium oxide
Explanation:
The movement of rock pieces and other materials on earth's surface is called Weathering
Answer: The products usually weigh more than the reactants.
Explanation:
Answer: The vapor pressure of the solution at is 137 torr
Explanation:
As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
The formula for relative lowering of vapor pressure will be,
where,
= relative lowering in vapor pressure
i = Van'T Hoff factor = 1 (for non electrolytes)
= mole fraction of solute =
Given : 13.06 g of napthalene is present in 100 g of solution, thus (100-13.06) g = 86.94 g of hexane
moles of solute (napthalene) =
moles of solvent (hexane) =
Total moles = moles of solute (napthalene) + moles of solvent (hexane) = 0.102 + 1.01 = 1.112
= mole fraction of solute (napthalene) =
Thus the vapor pressure of the solution at is 137 torr