All categories

3 years ago

If 11.2 g of naphthalene, C10H8, is dissolved in 107.8 g of chloroform, CHCl3, what is the molality of the solution?

Chemistry

1 answer:

Art [367]3 years ago

5 0

Answer: 0.811m

Explanation: Molarity is the moles of solute present per kg of solvent.

Molar mass of C10H8 = . 128.17 g/mol

No. of moles = given mass/molar mass

11.2g C10H8 = 11.2/128.17 g/mol C10H8

= 0.0874 mol C10H8

NOW 107.8g solvent (chloroform) contains 0.0879 molecules (naphthalene)

1000g '' will contain (0.0879/107.8 x 1000) mole solute

= 0.811 mole

Molarity of the solution is 0.811 m (option A)

You might be interested in

Which describes the molecule below?

Ira Lisetskai [31]

C. A lipid with three unsaturated fatty acids.
(got the question correct on a test)

4 0

2 years ago

The circles in the model represent atmospheric layers. Make each description with the correct name of each layer.

Masja [62]

Answer:

The bottom is troposhere the next is sratoshere,mesosphere,thermosphere then exoshere

Explanation:

6 0

3 years ago

If a piece of cadmium with a mass of 37.60 g and a temperature of 100.0 oC is dropped into 25.00 cc of water at 23.0 oC, what wi

zlopas [31]

Answer:

$T_{eq}=28.9\°C$

Explanation:

Hello!

In this case, since it is observed that hot cadmium is placed in cold water, we can infer that the heat released due to the cooling of cadmium is gained by the water and therefore we can write:

$Q_{Cd}+Q_{W}=0$

Thus, we insert mass, specific heat and temperatures to obtain:

$m_{Cd}C_{Cd}(T_{eq}-T_{Cd})+m_{W}C_{W}(T_{eq}-T_{W})=0$

In such a way, since the specific heat of cadmium and water are respectively 0.232 and 4.184 J/(g °C), we can solve for the equilibrium temperature (the final one) as shown below:

$T_{eq}=\frac{m_{Cd}C_{Cd}T_{Cd}+m_{W}C_{W}T_{W}}{m_{Cd}C_{Cd}+m_{W}C_{W}}$

Now, we plug in to obtain:

$T_{eq}=\frac{37.60g*0.232\frac{J}{g\°C}*100.00\°C+25.00g*4.184\frac{J}{g\°C}*23.0\°C}{37.60g*0.232\frac{J}{g\°C}+25.00g*4.184\frac{J}{g\°C}}\\\\T_{eq}=28.9\°C$

NOTE: since the density of water is 1g/cc, we infer that 25.00 cc equals 25.00 g.

Best regards!

6 0

2 years ago

Four animals were fleeing from a wildfire. All of them were running at a speed of 30 miles per hour. Which one has the greatest

RUDIKE [14]

Answer: I don’t know lol

Explanation: I am so sorry I thought this was easy

6 0

2 years ago

Read 2 more answers

At the county fair, Carrie and Sam climbed up on the carousel horses. Around and around they went; the horses also bobbed up and

grigory [225]

I believe sam's response is correct.
When human is riding a moving target with constant speed over a period of time, we tend to have a visual acceleration perception due to our optical movement.
This make people such as Carrie believes that the carousel horses are accelerating while it actually stayed at constant pace.

3 0

2 years ago