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When 1.045 g of CaO is added to 50.0 mL of water at 25.0 °C in a calorimeter, the temperature of the water increases to 32.3 °C.

Rus_ich [418]

Answer:

1.71 kJ/mol

Explanation:

The expression for the calculation of the enthalpy change of a process is shown below as:-

$\Delta H=m\times C\times \Delta T$

Where,

$\Delta H$ is the enthalpy change

m is the mass

C is the specific heat capacity

$\Delta T$ is the temperature change

Thus, given that:-

Mass of CaO = 1.045 g

Specific heat = 4.18 J/g°C

$\Delta T=32.3-25.0\ ^0C=7.3\ ^0C$

So,

$\Delta H=1.045\times 4.18\times 7.3\ J=31.88713\ J$

Also, 1 J = 0.001 kJ

So,

$\Delta H=0.03189\ kJ$

Also, Molar mass of CaO = 56.0774 g/mol

$Moles=\frac{Mass}{Molar\ mass}=\frac{1.045}{56.0774}\ mol=0.01863\ mol$

Thus, Enthalpy change in kJ/mol is:-

$\Delta H=\frac{0.03189}{0.01863}\ kJ/mol=1.71\ kJ/mol$

8 0

3 years ago

Question 1-19

Hunter-Best [27]

The experiment involving the determination of the number of ice cubes required to keep the temperature of the glass under 15 degrees Celcius, the following things have to be kept in mid:

The temperature of the surroundings
The initial temperature of the glass
The number of ice cubes added to the water in the glass

In order to keep into consideration the changing environmental temperatures (which is a variable in the experiment), the experiment had to be conducted daily to get accurate results keeping into consideration all the factors.

brainly.com/question/11256472

7 0

2 years ago

Does Radiant Energy contain Kinetic, or potential energy or both?

Jet001 [13]

Answer:

kinetic

Explanation:

8 0

3 years ago

suppose that you are comparing several objects. is it correct to say that the object with the largest volume has the largest mas

Semmy [17]

Answer:

No

Explanation:

It is not correct to say that an object with the largest volume has the largest mass.

Mass and volume are not directly related. In fact, the relationship between them can be direct or inverse.

Mass is the amount of matter in a substance. Volume is the space a body occupies.

A balloon and a stone for example is a typical one.
A balloon has more volume but far lesser mass compared to a stone.
A stone, gravel sized has low volume but more massive than a balloon.

Therefore, it is wrong to say a balloon has more mass because it has more volume.

3 0

3 years ago

What is the relative rate of diffusion of hydrogen and nitrogen

vredina [299]

Answer:

2.645

Explanation:

Rate of diffusion formula:

Sqrt(mass2/mass1)

>>sqrt(14/2)

(Note:Hydrogen must exist in dwiatomic, [H2])

3 0

2 years ago