1) (C2H5)2CBrCH2CH3 is the answer
explaiation:-
so when HBr is added to an alkene , according to the Markonicoff's rule ...H atoms are bonded to the C containing the most amount of H and Br is added to the other C.
2) Just add alkoholic KOH∆
One mole of a substance is defined by Avogadro as consisting of 6.022 x 1023 atoms. This is Avogadro's number. To calculate the number of atoms in two moles of sodium, use dimensional analysis. 2.0 moles Na x 6.022⋅1023g1mol=1.20⋅1024 atoms of Na
When cohesive force is stronger than the adhesive force: concave up meniscus, water forms droplets on surface
According to Raoult's law the relative lowering of vapour pressure of a solution made by dissolving non volatile solute is equal to the mole fraction of the non volatile solute dissolved.
the relative lowering of vapour pressure is the ratio of lowering of vapour pressure and vapour pressure of pure solvent

Where
xB = mole fraction of solute=?

p = 22.8 torr

mole fraction is ratio of moles of solute and total moles of solute and solvent
moles of solvent = mass / molar mass = 500 /18 = 27.78 moles
putting the values




mass of glucose = moles X molar mass = 1.218 X 180 = 219.24 grams