Vant hoff factor for ionic solute is the number of ions that are present in a solution. The equation for the ionization of calcium nitrate follows:

$Ca(NO_3)_2(aq.)\rightarrow Ca^{2+}(aq.)+2NO_3^-(aq.)$

The total number of ions present in the solution are 3.

To calculate the molality of solution, we use the equation:

$Molality=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ in grams}}$

Where,

$m_{solute}$ = Given mass of solute $(Ca(NO_3)_2)$ = 11.3 g

$M_{solute}$ = Molar mass of solute $(Ca(NO_3)_2)$ = 164 g/mol

$W_{solvent}$ = Mass of solvent (water) = 115 g

Putting values in above equation, we get:

$\text{Molality of }Ca(NO_3)_2=\frac{11.3\times 1000}{164\times 115}\\\\\text{Molality of }Ca(NO_3)_2=0.599m$

To calculate the depression in freezing point, we use the equation:

$\Delta T=iK_fm$

where,

i = Vant hoff factor = 3

$K_f$ = molal freezing point depression constant = 1.86°C/m.g

m = molality of solution = 0.599 m

Putting values in above equation, we get:

$\Delta T=3\times 1.86^oC/m.g\times 0.599m\\\\\Delta T=3.34^oC$

Depression in freezing point is defined as the difference in the freezing point of water and freezing point of solution.

$\Delta T=\text{freezing point of water}-\text{freezing point of solution}$

$\Delta T$ = 3.34 °C

Freezing point of water = 0°C

Freezing point of solution = ?

Putting values in above equation, we get:

$3.34^oC=0^oC-\text{Freezing point of solution}\\\\\text{Freezing point of solution}=-3.34^oC$

Hence, the freezing point of solution is -3.34°C

4 0

4 years ago

According to which calendar is new year’s celebrated on january 1st?

Sholpan [36]

Answer:

Gregorian calendar

Explanation:

Some types of calendar available are

Gregorian calendar
Julian calendar
Islamic calendar
Solar Hijri calendar
Hebrew calendar

Gregorian calendar: January 1st is new year and it the most widely used calendar in the world.

Julian calendar: January 14th is new year.

Islamic calendar: it follow the phase of the moon and those not regard seasons.

Solar hijri calendar: 21st of March is new year.

Hebrew calendar: 18th September will be the new year for 2020 in the Hebrew calendar.

5 0

3 years ago

A bike is traveling to the left with the speed of 27 m/s when the rider slams on the brakes. The bike skids for 41.5 m with the

Darina [25.2K]

The acceleration of the bike is equal to $8.78\frac{m}{s^{2}}$ opposing the movement (to the right).

Why?

Since after the rider slams the brakes, the bike came to a stop, we know that the acceleration is opposite to the velocity/movement.

We can use the following equation to calculate the acceleration:

$v_{f}^{2}=v_{o}^{2}+2*a*d$

So, substituting, we have: (let's consider negative to the left and positive to the right)

$0=(-27\frac{m}{s} )^{2}+2*a*41.5m\\\\0=729\frac{m^{2} }{s^{2} }+83*a\\\\a=\frac{-729\frac{m^{2}}{s^{2}}}{83m}=-8.78\frac{m}{s^{2}}$

The negative sign means that the acceleration's direction is opposite to the movement.

Hence, we have that the acceleration is equal to $8.78\frac{m}{s^{2}}$ opposing the movement (to the right).

Have a nice day!

5 0

4 years ago

Read 2 more answers

During fuel burn, the vertically launched terrier-sandhawk rocket had an acceleration of 300 m/s2 (about 30 times free-fall acce

quester [9]

Vertical acceleration = 300 m/s²
Initial vertical velocity = 0
Time of flight = 8.0 s

Calculate the height after 8 s.
h = (1/2)*(300 m/s²)*(8.0 s)² = 9600 m

Answer: 9600 m

3 0

3 years ago