Answer: The activation energy Ea for this reaction is 22689.8 J/mol
Explanation:
According to Arrhenius equation with change in temperature, the formula is as follows.
![ln \frac{k_{2}}{k_{1}} = \frac{-E_{a}}{R}[\frac{1}{T_{2}} - \frac{1}{T_{1}}]](https://tex.z-dn.net/?f=ln%20%5Cfrac%7Bk_%7B2%7D%7D%7Bk_%7B1%7D%7D%20%3D%20%5Cfrac%7B-E_%7Ba%7D%7D%7BR%7D%5B%5Cfrac%7B1%7D%7BT_%7B2%7D%7D%20-%20%5Cfrac%7B1%7D%7BT_%7B1%7D%7D%5D)
 = rate constant at temperature
 = rate constant at temperature  =
 = 
 = rate constant at temperature
 = rate constant at temperature  =
 =  
 = activation energy = ?
= activation energy = ?
R= gas constant = 8.314 J/kmol
 = temperature =
 = temperature = 
 = temperature =
 = temperature = 
Putting in the values ::
![ln \frac{4.8\times 10^8}{2.3\times 10^8} = \frac{-E_{a}}{8.314}[\frac{1}{649} - \frac{1}{553}]](https://tex.z-dn.net/?f=ln%20%5Cfrac%7B4.8%5Ctimes%2010%5E8%7D%7B2.3%5Ctimes%2010%5E8%7D%20%3D%20%5Cfrac%7B-E_%7Ba%7D%7D%7B8.314%7D%5B%5Cfrac%7B1%7D%7B649%7D%20-%20%5Cfrac%7B1%7D%7B553%7D%5D)

The activation energy Ea for this reaction is 22689.8 J/mol
 
        
             
        
        
        
Two or more compounds that have same molecular formula but differ in the arrangement of atoms in molecule and thus posses different properties are known as isomers.
The molecular formula of pentane is  substituting one hydrogen from pentane with bromine results in the formation of monobromo derivatives of pentane having molecular formula,
 substituting one hydrogen from pentane with bromine results in the formation of monobromo derivatives of pentane having molecular formula,  .
.
The structure of monobromo derivatives of pentane that is 1-bromopentane, 2-bromopentane, and 3-bromopentane and having molecular formula,  is shown in the image.
 is shown in the image.
The other two arrangements of monobromo derivatives of pentane that is 2-bromo-2-methylbutane and 2-bromo-3-methylbutane is shown in the image. 
There are different structures of monobromo derivatives of pentane having molecular formula,  which contain a 4-carbon chain are 1- bromo-2-methylbutane and 1-bromo-3-methylbutane shown in the image.
 which contain a 4-carbon chain are 1- bromo-2-methylbutane and 1-bromo-3-methylbutane shown in the image.
 
        
             
        
        
        
A mile.
For reference, it's about 1,607 or so meters, and 1km is 1,000.
 
        
                    
             
        
        
        
Answer:
The weight-average molar mass of polystyrene is 134,160 g/mol.
Explanation:
Molar mass of the monomer styrene ,  , M=104 g/mol
, M=104 g/mol
Given , number average molar mass of the polymer , M'= 89,440 g/mol
Degree of polymerization = n

The weight-average molar mass = 
Molar mass dispersity is ratio of weight-average molar mass to the number average molar mass of the polymer.



The weight-average molar mass of polystyrene is 134,160 g/mol.
 
        
             
        
        
        
Answer:
Fe₂O₃
Explanation:
To solve this question we must find the moles of Iron in 1.68g. With the difference of the masses we can find the moles of oxygen. The formula will be obtained with the ratio of both amount of moles:
<em>Moles Fe:</em>
1.68g * (1mol / 56g)  =0.03moles
<em>Moles O:</em>
2.40g-1.68g = 0.72g * (1mol/16g) = 0.045moles
The ratio O/Fe is:
0.045moles / 0.03moles = 1.5 moles. this ratio is obtained if the formula is:
<h3>Fe₂O₃</h3>