how are acids and proteins related?

hey guys i def recommend studying, but I know it gets hard sometimes so here's the answers:

1. C An acid can donate protons to a base when they react.
2. D The substance with the lower pH has 1,000 times as many hydrogen ions per volume of water.
3. D HCl is an acid, and Cl– is its conjugate base.
4. Electronegativity increases from left to right within a row of the periodic table.
5. A 1.0 × 10-7 mol/L
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