Answer:
A
Explanation:
it has an arrow symbolizing direction because a vector quantity has both magnitude and direction.
 
        
                    
             
        
        
        
Answer:
Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation.
Explanation:
The benzene ring in itself does not easily undergo electrophilic substitution reaction. Some groups activate or deactivate the benzene ring towards electrophilic substitution reactions. 
-NO2 ia a highly deactivating substituent therefore, Friedel-Crafts alkylation of nitrobenzene does not take place under any conditions.
This reaction scheme is therefore flawed because Nitrobenzene is too deactivated (by the nitro group) to undergo a Friedel-Crafts alkylation.
 
        
             
        
        
        
Answer:
You should follow these steps:
Count each type of atom in reactants and products. 
Place coefficients, as needed, in front of the symbols or formulas to increase the number of atoms or molecules of the substances.
Repeat steps 1 and 2 until the equation is balanced.
Explanation:
 
        
             
        
        
        
Answer:
3.79 x 10²⁴atoms
Explanation:
Given parameters: 
Number moles of lead  = 6.3moles 
Unknown: 
Number of atoms  = ? 
Solution: 
To solve this problem, 
               1 mole of a substance contains  6.02 x 10²³ atoms 
             6.3 mole of Pb  will contain 6.3  x 6.02 x 10²³ = 3.79 x 10²⁴atoms