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!
Metals usually become cations since electrons are negatively charged and when they are lost there are more protons than electrons making a positive net charge in the atom. (cations are positively charged ions while anions are negatively charged ions)
I hope this helps. Let me know if anything is unclear.
Answer: The look of the Earth has changed over time but continents have always been part of the picture. They didn't always look the way they do today, but yes, there have always been continents on Earth. Earth's continents are constantly in motion, and by running the tape ... against southern Europe, while the Atlantic will be a far wider ocean than it is today. ... During the war, Hess had used sonar to map some areas of the ocean floor in detail. ... away from both sides of the mid-ocean ridge at the same rate.
Answer : The concentration of the NaOH solution is, 0.738 M
Explanation :
To calculate the concentration of base, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:


Thus, the concentration of the NaOH solution is, 0.738 M