Answer : The enthalpy change of dissolution of
is 54.3 kJ/mole
Explanation :
Heat released by the reaction = Heat absorbed by the calorimeter + Heat absorbed by the water
![q=[q_1+q_2]](https://tex.z-dn.net/?f=q%3D%5Bq_1%2Bq_2%5D)
![q=[c_1\times \Delta T+m_2\times c_2\times \Delta T]](https://tex.z-dn.net/?f=q%3D%5Bc_1%5Ctimes%20%5CDelta%20T%2Bm_2%5Ctimes%20c_2%5Ctimes%20%5CDelta%20T%5D)
where,
q = heat released by the reaction
= heat absorbed by the calorimeter
= heat absorbed by the water
= specific heat of calorimeter = 
= specific heat of water = 
= mass of water = 107.70 g
= change in temperature = 
Now put all the given values in the above formula, we get:
![q=[(1.55J/^oC\times 2.46^oC)+(107.70g\times 4.184J/g^oC\times 2.46^oC)]](https://tex.z-dn.net/?f=q%3D%5B%281.55J%2F%5EoC%5Ctimes%202.46%5EoC%29%2B%28107.70g%5Ctimes%204.184J%2Fg%5EoC%5Ctimes%202.46%5EoC%29%5D)

Now we have to calculate the enthalpy change of dissolution of 

where,
= enthalpy change = ?
q = heat released = 1.1123 kJ
m = mass of
= 2.84 g
Molar mass of
= 138.55 g/mol


Therefore, the enthalpy change of dissolution of
is 54.3 kJ/mole
Answer:
Number of molecules = 1.8267×10^20
Explanation:
From the question, we can deuced that the gases behave ideally, the we can make use of the ideal gas equation, which is expressed below;
PV = nRT
where
P =pressure
V =volume
n = the number of moles
R is the gas constant equal to 0.0821 L·atm/mol·K
T is the absolute temperature
Given:
P = 6.75 atm;
T = 290.0 k,
; V = 1.07 cm³ = 0.001 L
( 6.75 atm)(0.00107 L) = n(0.0821 L·atm/mol·K)(290K)
n = 3.0335167*10^-4 moles
But there are 6.022×10²³ molecules in 1 mole,
Number of molecules = 1.8267×10^20
Answer:
The mechanical energy produced on burning fossil fuels is transformed into chemical energy stored in carbon dioxide.
Explanation:
When fossil fuels are burnt, mechanical energy is produced. Remember that according to the first law of thermodynamics, energy is neither created nor destroyed but can be transformed from one form to another. Hence the mechanical energy produced when fossil fuels are burnt for industrial use, heating of homes, electricity generation , cooking etc the mechanical energy produced is not 'lost'. It must be transformed in to another form of energy.
In the image the arrow G----> C, shows the mechanical energy produced when fossil fuels are burnt are stored as chemical energy in CO2 bonds. CO2 is found in the atmosphere, hence the arrow point upwards from the source towards the atmosphere (C is the atmospheric reservoir of CO2). The energy is subsequently used by producers to produce chemical energy stored in food.
Explanation:
It is known that the maximum value of ml is equal to the vale of l. But the minimum value of n is as follows.
n = l + 1
where, n = principle quantum number
l = azimuthal quantum number
Values of n can be 1, 2, 3, 4 and so on. Whereas the values of l can be 0, 1, 2, 3, and so on.
Also, "m" is known as magnetic quantum number whose values can be equal to -l and +l.
So, when n = 1 then l = 0 and m = 0.
When n = 2 then l = 1 and values of m will be equal to -1, 0, +1. As it is given that the magnetic quantum number ml = -1. Hence, it is only possible when n = 2.
Thus, we can conclude that the smallest possible value of the principal quantum number n of the state is 2.