1.326 grams of NH3 are required to produce 4.65 g of HF.
Step-by-step explanation:
Balanced chemical reaction is written first to know the number of moles taking part in original reaction.
 NH3 +3 F2 ⇒3 HF  +  NF3
Given:
mass of HF = 4.65
 First the number of moles of HF in 4.65 grams is calculated by using the formula:
number of moles (n) = 
atomic mass of HF = 20 grams/mole
putting the values in the above equation number of moles can be found.
n = 
   = 0.235 moles of HF are given.
From the equation it can be said that:
1 mole of NH3 reacts to form 3 moles of HF
so, x moles of NH3 would react to form 0.235 moles of HF
 =
 = 
3x = 0.235
x = 
x = 0.078 moles of NH3 is required.
The moles are converted to mass by applying the formula:
mass = atomic mass X number of moles (atomic mass of NH3 = 17 grams/mole)
         putting the values in the formula 
mass = 17 X 0.078 
 mass = 1.326 grams
 
        
             
        
        
        
Answer:
(9,-3)
Step-by-step explanation:
 
        
             
        
        
        
Yeah I’m also not %100 but I agree with the first person, #3
        
             
        
        
        
Answer:
Linear pair.
Step-by-step explanation:
 
        
             
        
        
        
Answer:

Step-by-step explanation:
For this case we have the following expression:

We need to remember that the natural log and the exponentiation with the base the euler number e are inverse operations, and if we apply exponentiation on both sides of the equation we got this:

We have the identity operator for this 

And that would be our final answer for this case.