The group 7A elements are called Halogens. 
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Answer:
The answer to your question is:
Explanation:
Data
moles H=?
moles of N = 0.0969
moles of NH₃=?
                             N₂ (g)  + 3 H₂ (g)  ⇒   2NH₃ (g)
Process
1.- Set a rule of three to calculate the moles of hydrogen
                          1 mol of nitrogen  -------------   3 moles of hydrogen
                          0.0969 moles of N ----------     x
                          x = (0.0969 x 3) / 1
                          x = 0.2907 moles of hydrogen          
2.- Set a rule of three to calculate the moles of ammonia
                         1 mol of nitrogen --------------  2 moles of ammonia
                         0.0969 mol of N --------------   x
                         x = (0.0969 x 2) / 1
                         x = 0.1938 moles of ammonia                 
 
        
             
        
        
        
Answer:
402.7897
Explanation:
Pretty sure but not 100% about it. 
grams in 2 pounds = 907.184 * specific heat of iron = .444
=402.789696
 
        
             
        
        
        
Answer is: pH value of solution of NaC₂H₃O₂ is 9.07.
Chemical reaction: C₂H₃O₂⁻ + H₂O ⇄ HC₂H₃O₂ + OH⁻.
Ka(HC₂H₃O₂) = 1,8·10⁻⁵.<span>
Ka · Kb = Kw.
</span>1,8·10⁻⁵ mol/dm³ · Kb = 1·10⁻¹⁴ mol²/dm⁶; the ionic product of water at 25°C.<span>
Kb(</span>C₂H₃O₂⁻)
= 1·10⁻¹⁴ mol²/dm⁶ ÷ 1,8·10⁻⁵ mol/dm³.<span>
Kb(</span>C₂H₃O₂⁻) =
5,56·10⁻¹⁰ mol/dm³.
c(C₂H₃O₂⁻) = 0,25 M.
[OH⁻] = [HC₂H₃O₂] = x.
[C₂H₃O₂⁻] = 0,25 M - x.
Kb = [OH⁻] · [HC₂H₃O₂] / [C₂H₃O₂⁻].
5,56·10⁻¹⁰ = x² / (0,25 M -x).
Solve quadratic equation: x = [OH⁻] = 0,0000118 M.
pOH = -log[OH⁻] = -log(0,0000118M) = 4,93.
pH + pOH = 14.
pH = 14 - 4,93 = 9,07.