<u>Answer:</u>
D<u>ispersion force :</u> is the weakest intermolecular force. The London dispersion force is a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make form temporary dipoles. This force is also called an induced dipole-induced dipole attraction because one molecule induce dipole in other molecule. London forces are the attractive forces that cause non polar substances to condense to liquids and to freeze into solids when the temperature is lowered sufficiently.
<u>Molecular size
:</u>
•Larger and heavier atoms and molecules exhibit stronger dispersion forces than lighter and smaller ones.
•In a larger atom or molecule, the valence electrons are, farther from the nuclei than in a smaller atom or molecule. They are less tightly bounded and can more easily form temporary dipoles.
<u>Molecular shape:
</u>
•At room temperature, neopentane (C5H12) is a gas whereas n-pentane (C5H12) is a liquid.
•London dispersion forces between n-pentane molecules are stronger than those between neopentane molecules even though both molecules are nonpolar and have the same molecular weight.
•The somewhat cylindrical shape of n-pentane molecules allows them to come in contact with each other more effectively than the somewhat spherical neopentane molecules.
so here
,
2 > 3 > 1 > 4 > 5 > 6
1st have more dispersion force because it is n heptane present in liquid form.
6th have lowest force because it is present in gaseous form.
Answer:
Alright love it would be --- B. Neutron
Answer: (2) releases 2260 J/g of heat energy
Explanation:
Latent heat of vaporization is the amount of heat required to convert 1 mole of liquid to gas at atmospheric pressure.
Latent heat of condensation is energy released when 1 mole of vapor condenses to form liquid droplets.
The temperature does not change during this process, so heat released goes into changing the state of the substance, thus it is called latent which means hidden. The energy released in this process is same in magnitude as latent heat of vaporization. The heat of condensation of water vapour is about 2,260 J/g.
Answer:
The value of the activation energy is 240.96 kJ/mol.
Explanation:
According to the Arrhenius equation,
![k=A\times e^{\frac{-Ea}{RT}}](https://tex.z-dn.net/?f=k%3DA%5Ctimes%20e%5E%7B%5Cfrac%7B-Ea%7D%7BRT%7D%7D)
![\ln k=-\frac{E_a}{RT}+\ln A](https://tex.z-dn.net/?f=%5Cln%20k%3D-%5Cfrac%7BE_a%7D%7BRT%7D%2B%5Cln%20A)
![\log k=-\frac{E_a}{2.303RT}+\log A](https://tex.z-dn.net/?f=%5Clog%20k%3D-%5Cfrac%7BE_a%7D%7B2.303RT%7D%2B%5Clog%20A)
The graph between log(k) and (1/T) will give straight line with negative slope along with the intercept corresponding to the value of A.
Slope f the line =
The slope of the line :
![=\frac{\log (k_2)-\log(k_1)}{\frac{1}{T_2}-\frac{1}{T_1}}](https://tex.z-dn.net/?f=%3D%5Cfrac%7B%5Clog%20%28k_2%29-%5Clog%28k_1%29%7D%7B%5Cfrac%7B1%7D%7BT_2%7D-%5Cfrac%7B1%7D%7BT_1%7D%7D)
![T_1=600^oC=600+273K=873 K](https://tex.z-dn.net/?f=T_1%3D600%5EoC%3D600%2B273K%3D873%20K)
![k_1=1.87\times 10^{-3} (Ms)^{-1}](https://tex.z-dn.net/?f=k_1%3D1.87%5Ctimes%2010%5E%7B-3%7D%20%28Ms%29%5E%7B-1%7D)
![T_2=650^oC=650+273K=923K](https://tex.z-dn.net/?f=T_2%3D650%5EoC%3D650%2B273K%3D923K)
![k_2=0.0113 (Ms)^{-1}](https://tex.z-dn.net/?f=k_2%3D0.0113%20%28Ms%29%5E%7B-1%7D)
![-\frac{E_a}{2.303R}=\frac{\log (k_2)-\log(k_1)}{\frac{1}{T_2}-\frac{1}{T_1}}](https://tex.z-dn.net/?f=-%5Cfrac%7BE_a%7D%7B2.303R%7D%3D%5Cfrac%7B%5Clog%20%28k_2%29-%5Clog%28k_1%29%7D%7B%5Cfrac%7B1%7D%7BT_2%7D-%5Cfrac%7B1%7D%7BT_1%7D%7D)
![-\frac{E_a}{2.303\times 8.314J/K mol}=\frac{\log (0.0113 (Ms)^{-1})-\log(1.87\times 10^{-3} (Ms)^{-1})}{\frac{1}{923 K}-\frac{1}{873 K}}](https://tex.z-dn.net/?f=-%5Cfrac%7BE_a%7D%7B2.303%5Ctimes%208.314J%2FK%20mol%7D%3D%5Cfrac%7B%5Clog%20%280.0113%20%28Ms%29%5E%7B-1%7D%29-%5Clog%281.87%5Ctimes%2010%5E%7B-3%7D%20%28Ms%29%5E%7B-1%7D%29%7D%7B%5Cfrac%7B1%7D%7B923%20K%7D-%5Cfrac%7B1%7D%7B873%20K%7D%7D)
![-E_a=-240,959.466J/mol](https://tex.z-dn.net/?f=-E_a%3D-240%2C959.466J%2Fmol)
![E_a=240,959.466 J/mol=240.96 kJ/mol](https://tex.z-dn.net/?f=E_a%3D240%2C959.466%20J%2Fmol%3D240.96%20kJ%2Fmol)
The value of the activation energy is 240.96 kJ/mol.
Answer:
Molar mass of NH3,
MM = 1*MM(N) + 3*MM(H)
= 1*14.01 + 3*1.008
= 17.034 g/mol
mass(NH3)= 25.0 g
use:
number of mol of NH3,
n = mass of NH3/molar mass of NH3
=(25 g)/(17.03 g/mol)
= 1.468 mol
Molar mass of O2 = 32 g/mol
mass(O2)= 35.8 g
use:
number of mol of O2,
n = mass of O2/molar mass of O2
=(35.8 g)/(32 g/mol)
= 1.119 mol
The balanced chemical equation is:
4 NH3 + 5 O2 ---> 4 NO + 6 H2O
4 mol of NH3 reacts with 5 mol of O2 for 1.468 mol of NH3, 1.835 mol of O2 is required
But we have 1.119 mol of O2
so, O2 is limiting reagent
we will use O2 in further calculation
Molar mass of NO,
MM = 1*MM(N) + 1*MM(O)
= 1*14.01 + 1*16.0
= 30.01 g/mol
According to balanced equation
mol of NO formed = (4/5)* moles of O2
= (4/5)*1.119 = 0.895 mol
use: mass of NO = number of mol * molar mass
= 0.895*30.01
= 26.86 g
Answer: 26.9 g