Actually, I strongly believe it is a switch.
<u>Answer: </u>The molar mass of solute is 115 g/mol.
<u>Explanation:</u>
Elevation in the boiling point is defined as the difference between the boiling point of the solution and the boiling point of the pure solvent.
The expression for the calculation of elevation in boiling point is:

OR
......(1)
where,
Boiling point of pure solvent (benzene) = 
Boiling point of solution = 
i = Vant Hoff factor = 1 (for non-electrolytes)
= Boiling point elevation constant = 
= Given mass of solute = 10 g
= Molar mass of solute = ? g/mol
= Mass of solvent = 200 g
Putting values in equation 1, we get:

Hence, the molar mass of solute is 115 g/mol.
Answer:
(D) Neither I nor II
Explanation:
The reagent potassium hydrogen phthalate is found in pure form and it is not partially hydrated .
The pallet form of NaOH ( solid form ) absorbs carbon dioxide gas from the atmosphere but NaOH in solution form does not absorb carbon dioxide .
Hence option D ) is right choice .
Answer:
The law of multiple proportions is the third postulate of Dalton's atomic theory. It states that the masses of one element which combine with a fixed mass of the second element are in a ratio of whole numbers.
Therefore, the masses of oxygen in the two compounds that combine with a fixed mass of carbon should be in a whole number ratio. In 100 grams of the first compound (100 is chosen to make calculations easier), there are 57.1 grams oxygen and 42.9 grams carbon. The mass of oxygen (O) per gram of carbon (C) is:
57.1 g O / 42.9 g C = 1.33 g O per g C
In the 100 grams of the second compound, there are 72.7 grams of oxygen (O) and 27.3 grams of carbon (C). The mass of oxygen per gram of carbon is:
72.7 g O / 27.3 g C = 2.66 g O per g C
Dividing the mass O per g C of the second (larger value) compound:
2.66 / 1.33 = 2
This means that the masses of oxygen that combine with carbon are in a 2:1 ratio. The whole-number ratio is consistent with the law of multiple proportions.
Explanation:
Most of the positively charged particles bounced back at a range of angles as they collided with the atoms in the foil; only a few passed straight through the foil. Therefore, scientists discovered<span> that every atom contains a nucleus where its positive charge and most of its mass are concentrated.</span>