Answer:
3.064 $
Solution:
First of all we will find the number of pounds contained by one Kg. Therefore, it is found that,
1 Kilogram = 2.20462 Pounds
Hence, as given,
1 Pound of Margarine costs = 1.39 Dollars
So,
2.20462 Pounds Margarine will cost = X Dollars
Solving for X,
X = (2.20462 Pounds × 1.39 Dollars) ÷ 1 Pound
X = 3.064 Dollars
The answer is , C. Both the atomic mass and the atomic number increase from left to right .
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
+
= 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
= 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.