D= M/V so, D=300/40 wich is 7.5 so D= 7.5g/m3
Answer : The molar mass of the solute will be
87.90 g/mol.Explanation : We know the formula for elevation in boiling point, which is
Δt = i

m
given that, Δt = 0.357,

= 5.02 and mass of

= 40,
on substituting the value we get,
0.357 = (1) X (5.02) X (x/ 0.044), on solving we get x = 2.844 X

.
Now, 0.250/ 2.844 X

=
87.90 g/mol. which is the weight of unknown component.
A Anything that has mass and takes up space
Answer:
0.453 moles
Explanation:
The balanced equation for the reaction is:
2Fe(s) + 3O2(g) ==> 2Fe2O3
From the equation, mass of O2 involved = 16 x 2 x 3 = 96g
mass of Fe2O3 involved = [(2x26) + 3 x 16] x 2
= 100g
Therefore 96g of O2 produced 100g of Fe2O3
32.2g of O2 Will produce 100x32.2/96
= 33.54g of Fe2O3
Converting it to mole using number of mole = mass/molar mass
but molar mass of Fe2O3 = 26 + (16 X 3)
= 74g/mole
Therefore number of mole of 33.54g of Fe2O3 = 33.54/74
= 0.453 moles