Explanation:
According to the Henderson-Hasselbalch equation, the relation between pH and 
is as follows.
pH = 
where, pH = 7.4 and = 7.21
As here, we can use the nearest to the desired pH.
So, 7.4 = 7.21 + 
0.19 =
= 1.55
1 mM phosphate buffer means ![[HPO_{4}]](https://tex.z-dn.net/?f=%5BHPO_%7B4%7D%5D)
+ ![[H_{2}PO_{4}]](https://tex.z-dn.net/?f=%5BH_%7B2%7DPO_%7B4%7D%5D)
= 1 mM
Therefore, the two equations will be as follows.
= 1.55 ............. (1)
+ = 1 mM ........... (2)
Now, putting the value of from equation (1) into equation (2) as follows.
1.55![[H_{2}PO_{4}] + [tex][H_{2}PO_{4}]](https://tex.z-dn.net/?f=%5BH_%7B2%7DPO_%7B4%7D%5D%20%2B%20%5Btex%5D%5BH_%7B2%7DPO_%7B4%7D%5D)
= 1 mM
2.55 = 1 mM
= 0.392 mM
Putting the value of in equation (1) we get the following.
0.392 mM + = 1 mM
= (1 - 0.392) mM
= 0.608 mM
Thus, we can conclude that concentration of the acid must be 0.608 mM.
Answer:
The 12L helium tank pressurized to 160 atm will fill <em>636 </em>3-liter balloons
Explanation:
It is possible to answer this question using Boyle's law:
Where P₁ is the pressure of the tank (160atm), V₁ is the volume of the tank (12L), P₂ is the pressure of the balloons (1atm, atmospheric pressure) And V₂ is the volume this gas will occupy at 1 atm, thus:
160atm×12L = 1atm×V₂
V₂ = 1920L
As the tank will never be empty, the volume of the gas able to fill balloons is the total volume minus 12L, thus the volume of helium able to fill balloons is:
1920L - 12L = 1908L
1908L will fill:
1908L×
= <em>636 balloons</em>
<em></em>
I hope it helps!
battery
bro look it up first and do some searching and if you don't get a answer then ask it up here your just gonna waste your points
Answer:
B)
an atom of mercury has a different mass than an atom of copper.
Explanation:
12.04moles
Explanation:
Given parameters:
Number of molecules = 7.25 x 10²⁴molecules
unknown:
Number of moles = ?
Solution:
The moles of a substance is the amount of substance that contains avogadro's number of particles:
1 mole of a substance = 6.02 x 10²³
x moles of the compound will contain: ![\frac{7.25 x 10[tex]^{24}](https://tex.z-dn.net/?f=%5Cfrac%7B7.25%20x%2010%5Btex%5D%5E%7B24%7D)
}{6.02 x 10
}[/tex] = 12.04moles
This gives 12.04moles
Learn more:
Number of moles brainly.com/question/1841136
#learnwithBrainly
