Calculate the pH of a solution that is 0.240 M in sodium formate (HCOONa) and 0.120 M in formic acid (HCOOH). Express your answer to two decimal places.

Answer : The  pH of the solution is, 4.0

Explanation : Given,

Acid dissociation constant for formic acid,

Concentration of formic acid (acid) = 0.120 M

Concentration of sodium formate (salt) = 0.240 M

First we have to calculate the value of .

The expression used for the calculation of is,

Now put the value of in this expression, we get:

Now we have to calculate the pH of buffer.

Using Henderson Hesselbach equation :

Now put all the given values in this expression, we get:

Thus, the pH of the solution is, 4.0

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.