For the reaction c5h5n(aq) + h2o(l) c5h5nh+(aq) + oh-(aq), which of the following is a conjugate acid-base pair?

a. c5h5n, c5h5nh+
b. c5h5nh+, oh-
c. h2o, oh-
d. c5h5n, h2o

b. ,

Explanation:

According to the Bronsted-Lowry conjugate acid-base theory, an acid is defined as a substance which looses donates protons and thus forming conjugate base and a base is defined as a substance which accepts protons and thus forming conjugate acid.

For the given chemical equation:

Here, is accepting a proton, thus it is considered as a base and after accepting a proton, it forms which is a conjugate acid.

And, is losing a proton, thus it is considered as an acid and after loosing a proton, it forms which is a conjugate base.

Hence, the correct answer is b. ,

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"

in the analysis of systems that involve fluid flow, we frequently encounter the combination of properties u and pv.