At what ph will ilepredominantly exist as a zwitterions

Question

1. A buffer is a chemical that can be used to make solutions that resist change in pH near the the buffer's pKa upon addition of an acid or a base.

• True
• False

2. Hydrogen is an atom with a high degree of electro negativity

• True
• False

3. A water molecule is not polar because:

1. Hydrogen and oxygen have similar electro negativity.
2. There is not unequal distribution of electrons because of the symmetry of this molecule.
3. The oxygen atom is not found on one "side" of the molecule.
4. Water is a polar molecule.
5. None of the above.

4. At what pH will Ilepredominantly exist as a zwitterions?

1. 2.36
2. 9.68
3. 1
4. 5.87
5. 12

5. Tyrosine is a hydroxyl containing amino acid that can be phosphorylated on this group.

• True
• False

6. D form amino acids commonly occur in proteins.

• True
• False