5.2e+26is it this? im not sure
Number 1 is C number 2 is B and number 3 is also B
Answer:
Mass percentage → 0.074 %
[F⁻] = 741 ppm
Explanation:
Aqueous solution of flouride → [F⁻] = 0.0390 M
It means that in 1L of solution, we have 0.0390 moles of F⁻
We need the mass of solution and the mass of 0.0390 moles of F⁻
Mass of solution can be determined by density:
1g/mL = Mass of solution / 1000 mL
Note: 1L = 1000mL
Mass of solution: 1000 g
Moles of F⁻ → 0.0390 moles . 19g /1 mol = 0.741 g
Mass percentage → (Mass of solute / Mass of solution) . 100
(0.741 g / 1000 g) . 100 = 0.074 %
Ppm = mass of solute . 10⁶ / mass of solution (mg/kg)
0.741 g . 1000 mg/1g = 741 mg
1000 g . 1 kg/1000 g = 1kg
741 mg/1kg = 741 ppm
Answer:
Percent yield = 90.8%
Explanation:
The reaction of Fe with S to produce FeS is:
Fe + S → FeS
<em>Where the moles of Fe added in excess of S are the moles of FeS</em>
<em />
Now, percent yield is defined as 100 times the ratio between actual yield (13.8g of FeS) and theoretical yield (15.2g FeS):
Percent yield = 13.8g / 15.2g * 100
<h3>Percent yield = 90.8%</h3>
Answer:
I should use a volumetric flask.
Explanation:
If the accuracy of the concentration is important, we need to use a volumetric flask.