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:
Part A:
First, convert molarity to moles by multiplying by the volume:
0.293 M AgNO3 = (0.293 moles AgNO3)/1 L x 1.19 L = 0.349 moles AgNO3
D, obviously. All living things are made of one or more cells, therefore non-living things aren’t made of cells
A: 2H₂ + O₂ → 2H₂O
H: 4 H:4
O: 2 O: 2
The equation is balanced.
B. 2S + 3O₂ → 2SO₃
S: 2 S: 2
O: 6 O: 6
The equation is balanced.
C. Li + Cl₂ → LiCl
Li: 1 Li: 1
Cl: 2 Cl: 1
The equation is not balanced.
2Li + Cl₂ → 2LiCl
Li: 2 Li: 2
Cl: 2 Cl: 2
D: 2K + 2H₂O → H₂ + 2KOH
K: 2 K: 2
H: 4 H: 4
O: 2 O: 2
The equation is balanced.
E: 2Fe + Cu(NO₃)₂ → 2Cu + Fe(NO₃)₂
Fe: 2 Fe: 1
Cu: 1 Cu: 2
N: 2 N: 2
O: 6 O: 6
The equation is not balanced.
2Fe + 2Cu(NO₃)₂ → 2Cu + 2Fe(NO₃)₂
Fe: 2 Fe: 2
Cu: 2 Cu: 2
N: 4 N: 4
O: 12 O: 12
The following equations that are balanced are A, B, and D.
