Answer:
91.26 g
Explanation:
Given data:
Mass of PF₃ = 180 g
Mass of F₂ required = ?
Solution:
Chemical equation:
P₄ + 6F₂ → 4PF₃
Moles of PF₃:
Number of moles = mass/ molar mass
Number of moles = 180 g/ 88 g/mol
Number of moles = 2.05 mol
Now we will compare the moles of PF₃ with F₂.
PF₃ : F₂
4 : 6
2.05 : 6/4×2.05 = 3.075
Mass of F₂:
Mass of F₂ = moles × molar mass
Mass of F₂ = 3.075 mol × 38 g/mol
Mass of F₂ = 116.85 g
If reaction yield is 78.1%:
116.85 /100 ×78.1 = 91.26 g
<span>a.the nearest 1 ml
1 mL is much more precise than 100 mL because 1 mL is a very small and precise unit of measurement</span>
PLEASE POST YOUR QUESTIONS IN ENGLISH, ANYONE CAN REPORT YOU FOR DOING THIS BE CAREFULL
Answer:
a: 1
b: 4.5x10⁻⁴
c: 1.125x10⁻⁶
[H₃O⁺] = 0.000859M
Explanation:
As HNO₂ is a weak acid, its equilibrium in water is:
HNO₂(aq) + H₂O(l) ⇄ H₃O⁺(aq) + NO₂⁻(aq)
Equilibrium constant, ka, is defined as:
ka = 4.5x10⁻⁴ = [H₃O⁺] [NO₂⁻] / [HNO₂] <em>(1)</em>
Equilibrium concentration of each specie are:
[HNO₂] = 0.00250M - x
[H₃O⁺] = x
[NO₂⁻] = x
Replacing in (1):
4.5x10⁻⁴ = x × x / 0.00250M - x
1.125x10⁻⁶ - 4.5x10⁻⁴x = x²
0 = x² + 4.5x10⁻⁴x - 1.125x10⁻⁶
As the quadratic equation is ax² + bx + c = 0
Coefficients are:
a: 1
b: 4.5x10⁻⁴
c: 1.125x10⁻⁶
Now, solving quadratic equation:
x = -0.0013 → False answer, there is no negative concentrations.
<em>x = 0.000859</em>
As [H₃O⁺] = x; <em>[H₃O⁺] = 0.000859M</em>
I hope it helps!
3.6 moles 
required when each quantity of reactant completely reacts.
The ratio of the mole quantities of any two compounds present in a balanced chemical reaction is known as the mole ratio. A reaction's product yield can be predicted using mole ratios, as can the amount of reactant required to produce a specific amount of result.
The balanced chemical equation is :
(l) → 
(g) + 
(g)
Given is = 2.6 mol 
As we see, 3 moles of reacts with 4 moles of .
Therefore,
n( ) = n( ) × 
n( ) = 
n( ) = 3.6 moles.
Therefores, 3.6 moles required when each quantity of reactant completely reacts.
Learn more about moles here;
brainly.com/question/20486415
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