Answer:
1. pH = 1.23.
2. 
Explanation:
Hello!
1. In this case, for the ionization of H2C2O4, we can write:

It means, that if it is forming a buffer solution with its conjugate base in the form of KHC2O4, we can compute the pH based on the Henderson-Hasselbach equation:
![pH=pKa+log(\frac{[base]}{[acid]} )](https://tex.z-dn.net/?f=pH%3DpKa%2Blog%28%5Cfrac%7B%5Bbase%5D%7D%7B%5Bacid%5D%7D%20%29)
Whereas the pKa is:

The concentration of the base is 0.347 M and the concentration of the acid is 0.347 M as well, as seen on the statement; thus, the pH is:

2. Now, since the addition of KOH directly consumes 0.070 moles of acid, we can compute the remaining moles as follows:

It means that the acid remains in excess yet more base is yielded due to the effect of the OH ions provided by the KOH; therefore, the undergone chemical reaction is:

Which is also shown in net ionic notation.
Best regards!
Answer:

Explanation:
Hello,
In this case, since the density is defined as the ratio between the mass and the volume as shown below:

We can compute the density of water for the given 43 g that occupy the volume of 43 mL:

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Sb has the largest atomic radius by 206
Answer:
The internal energy is the total amount of kinetic energy and potential energy of all the particles in the system. ... When the substance melts or boils, energy is put in to breaking the bonds that are holding particles together, which increases the potential energy.
Explanation: