An electron ______ is an area around the nucleus of an atom where an electron is likely to be found.

A solution is prepared by dissolving 27.0 g of urea [(NH2)2CO], in 150.0 g of water. Calculate the boiling point of the solution

andrew11 [14]

Answer: The boiling point of solution is 101.56°C

Explanation:

Elevation in boiling point is defined as the difference in the boiling point of solution and boiling point of pure solution.

The equation used to calculate elevation in boiling point follows:

$\Delta T_b=\text{Boiling point of solution}-\text{Boiling point of pure solution}$

To calculate the elevation in boiling point, we use the equation:

$\Delta T_b=iK_bm$

Or,

$\text{Boiling point of solution}-\text{Boiling point of pure solution}=i\times K_b\times \frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ (in grams)}}$

where,

Boiling point of pure water = 100°C

i = Vant hoff factor = 1 (For non-electrolytes)

$K_b$ = molal boiling point elevation constant = 0.52°C/m.g

$m_{solute}$ = Given mass of solute (urea) = 27.0 g

$M_{solute}$ = Molar mass of solute (urea) = 60 g/mol

$W_{solvent}$ = Mass of solvent (water) = 150.0 g

Putting values in above equation, we get:

$\text{Boiling point of solution}-100=1\times 0.52^oC/m\times \frac{27\times 1000}{60\times 150}\\\\\text{Boiling point of solution}=101.56^oC$

Hence, the boiling point of solution is 101.56°C

5 0

3 years ago

Balance equation P2O5 + H20 - - - - > H3PO4 Help me.....

Archy [21]

Answer:

Search by reactants (P 2O 5, H 2O) and by products (H 3PO 4)

H2O + P2O5 → H3PO4

H2O + HNO3 + P2O5 → H3PO4 + N2O5

8 0

2 years ago

C. Another radioisotope of americium exists which has an atomic mass of 242.

ollegr [7]

Answer:

1 g

Explanation:

The half-life of Am-242 (16 h) is the time it takes for half of it to disappear.

We can make a table of the mass left after each half-life.

$\begin{array}{cccc}\textbf{No. of} & & \textbf{Percent} & \textbf{Mass}\\\textbf{Half-lives} & \textbf{Time/h} & \textbf{Remaining} & \textbf{Remaining/g}\\0& 0 & 100 & 8\\1 & 16 &50 & 4\\2 & 32 & 25 & 2\\3 & 48 & 12.5 & 1\\4 & 64 & 6.25 & 0.5\\\end{array}$

The mass remaining after 48 h is 1 g.

7 0

2 years ago

in your notebook,write the appropriate tempo for the following actions.Then demostrate the actions then,demostrate the action in

pogonyaev

Answer:

cell :—

•They lack a well-defined nucleus, have a nucleoid instead.

•Usually have double-stranded, circular DNA.

•Do not have mitochondria.

Eukaryotic cell :—

•Have a well-defined nucleus enclosed in the nuclear membrane.

•Have a linear double-stranded nucleus.

•Mitochondria are present.

6 0

2 years ago

Predict, using Boyle’s Law, what will happen to a balloon that an ocean diver takes to a pressure of 202 kPa (normal atmospheric

kaheart [24]

Explanation:

Balloon that an ocean diver takes to a pressure of 202 k Pa will get reduced in size that is the volume of the balloon will get reduced. This is because pressure and volume of the gas are inversely related to each other.

According to Boyle's law: The pressure of the gas is inversely proportional to the volume occupied by the gas at constant temperature(in Kelvins).

$pressure\propto \frac{1}{volume}$ (At constant temperature)

The pressure beneath the sea is 202 kPa and the atmospheric pressure is 101.3 kPa . This increase in pressure will result in decrease in volume occupied by the gas inside the balloon with decrease in size of a balloon. Hence, the size of the balloon will get reduced at 202 kPa (under sea).

7 0

2 years ago