Answer:
102.26 moles of helium were required to Fill the Goodyear Blimp
Explanation:
To solve this question we need to use combined gas law:
PV = nRT
<em>Where P is pressure, V is volume of gas (2500L), n are moles of gas (Our incognite), R is gas constant (0.082atmL/molK) and T is absolute temperature</em>
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Assuming atmospheric condition we can write P = 1atm and T = 25°C = 298.15K
Replacing:
PV/RT = n
1atm*2500L / 0.082atmL/molK*298.15K = n
<h3>102.26 moles of helium were required to Fill the Goodyear Blimp</h3>
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Answer : The pH of the solution is, 9.63
Explanation : Given,
The dissociation constant for HCN = 
First we have to calculate the moles of HCN and NaCN.

and,

The balanced chemical reaction is:

Initial moles 0.1116 0.0461 0.08978
At eqm. (0.1116-0.0461) 0 (0.08978+0.0461)
0.0655 0.1359
Now we have to calculate the pH of the solution.
Using Henderson Hesselbach equation :
![pH=pK_a+\log \frac{[Salt]}{[Acid]}](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%20%5Cfrac%7B%5BSalt%5D%7D%7B%5BAcid%5D%7D)
Now put all the given values in this expression, we get:


Therefore, the pH of the solution is, 9.63
Answer:
50 g Sucrose
Explanation:
Step 1: Given data
- Concentration of the solution: 2.5%
Step 2: Calculate the mass of sucrose needed to prepare the solution
The concentration of the solution is 2.5%, that is, there are 2.5 g of sucrose (solute) every 100 g of solution. The mass of sucrose needed to prepare 2000 g of solution is:
2000 g Solution × 2.5 g Sucrose/100 g Solution = 50 g Sucrose
So we know the number of moles of each compound. If we need to know the concentration we must know the number of moles that the compounds react with...
Answer:
At the equivalence point, equal amounts of H+ and OH– ions will combine to form H2O, resulting in a pH of 7.0 (neutral). The pH at the equivalence point for this titration will always be 7.0, note that this is true only for titrations of strong acid with strong base.
Explanation: