The piece of evidence would suggest an unknown substance is an ionic compound is that it conducts electricity when dissolved in water.
Answer:
d) Interaction between Arg and Lys side chains at a pH of 7, assuming standard pKa values for Arg and Lys.
Explanation:
Arginine and Lysine are basic amino acids. They play same role in various membrane proteins. They both have high aqueous values which give rise to high electrostatic interaction. The interaction is mainly in the cations of the side chains. They both are heterologous secreted proteins which plays role of metabolite.
A.) half - life of a radioactive substance is defined as the time during which concentration of the substance becomes half the initial value.
A contact force is a force in which and object comes in contact with a another object. A non-contact force, is a force is an object applied by another body. (A good example of a non-contact force is gravity)
Answer is: a) in the presence of a base.
Phenolphthalein is colorless in acidic solutions and pink in basic solutions.
Acid-base indicators are usually weak acids or bases and they are chemical detectors for hydrogen or hydronium cations.
Example for acid-base indicator is phenolphthalein (molecular formula C₂₀H₁₄O₄).
When solution turns phenolphthalein pink, it means it is basic (pH>7).
