The answer for the following problem is described below.
<em><u> Therefore the standard enthalpy of combustion is -2800 kJ</u></em>
Explanation:
Given:
enthalpy of combustion of glucose(Δ of
 of  ) =-1275.0
) =-1275.0
enthalpy of combustion of oxygen(Δ of
 of  ) = zero
) = zero
enthalpy of combustion of carbon dioxide(Δ of
 of  ) = -393.5
) = -393.5
enthalpy of combustion of water(Δ of
 of  ) = -285.8
) = -285.8
To solve :
standard enthalpy of combustion
We know;
Δ = ∈Δ
  = ∈Δ (products) - ∈Δ
 (products) - ∈Δ (reactants)
 (reactants)
 (s) +6
 (s) +6  (g) → 6
(g) → 6  (g)+ 6
 (g)+ 6  (l)
(l)
Δ = [6 (-393.5) + 6(-285.8)] - [6 (0) + (-1275)]
 = [6 (-393.5) + 6(-285.8)] - [6 (0) + (-1275)]
Δ = [6 (-393.5) + 6(-285.8)] - [0 - 1275]
 = [6 (-393.5) + 6(-285.8)] - [0 - 1275]
Δ = 6 (-393.5) + 6(-285.8)  - 0 + 1275
 = 6 (-393.5) + 6(-285.8)  - 0 + 1275
Δ = -2361 - 1714 - 0 + 1275
 = -2361 - 1714 - 0 + 1275
Δ =-2800 kJ
 =-2800 kJ
<em><u> Therefore the standard enthalpy of combustion is -2800 kJ</u></em>
 
        
             
        
        
        
Are u sure this is the right option? Well, antimony can be decomposed. Including octane.
        
             
        
        
        
In which region is the substance in both the solid phase and the liquid phase ?
2
        
                    
             
        
        
        
Answer:
the concentration of free Ca2⁺ in this solution is 7.559 × 10⁻⁷
Explanation:
Given the data in the question;
 +
 +  ⇄
 ⇄  
Formation constant Kf
Kf =  / ( [
 / ( [ ][
][ ] ) = 5.0 × 10¹⁰
] ) = 5.0 × 10¹⁰
Now,
[ ] =
] =  ; ∝₄ = 0.35
; ∝₄ = 0.35
so the equilibrium is;
 +
 +  ⇄
 ⇄   + 4H⁺
 + 4H⁺
Given that;  =
 =  { 1 mol
     { 1 mol  reacts with 1 mol
  reacts with 1 mol  }
  }
so at equilibrium,  =
 =  = x
 = x
∴
 +
 +  ⇄
 ⇄  
x        + x         0.010-x
since Kf is high, them x will be small so, 0.010-x is approximately 0.010
so;
Kf =  / ( [
 / ( [ ][
][ ] ) =
] ) =   / ( [
 / ( [ ][
][ ] )  = 5.0 × 10¹⁰
] )  = 5.0 × 10¹⁰
⇒  / ( [
 / ( [ ][
][ ] )  = 5.0 × 10¹⁰
] )  = 5.0 × 10¹⁰
⇒ 0.010 / ( [x][ 0.35 × x] )  = 5.0 × 10¹⁰
⇒ 0.010 / 0.35x²  = 5.0 × 10¹⁰
⇒ x² = 0.010 / ( 0.35 × 5.0 × 10¹⁰ )
⇒ x² = 0.010 / 1.75 × 10¹⁰
⇒ x² = 0.010 / 1.75 × 10¹⁰ 
⇒ x² = 5.7142857 × 10⁻¹³ 
⇒ x = √(5.7142857 × 10⁻¹³)
⇒ x = 7.559 × 10⁻⁷
Therefore, the concentration of free Ca2⁺ in this solution is 7.559 × 10⁻⁷
 
        
             
        
        
        
Answer:
An educated guess based on what you already know.
Explanation: