Answer:
a. Work, ΔE is negative;
b. Work, ΔE is negative;
c. Work, ΔE is positive.
Explanation:
In the three cases, there is energy exchange in primarily work. The heat is the energy flow because of the difference in temperature. Of course, some heat may be lost in the cases by dissipation.
In the letter <em>a</em> the system is at an initial velocity different from 0, and then it stops. The energy that is represented here is the kinetic energy, which is the energy of the movement. Note that the system goes from a higher velocity to 0, so it is losing kinetic energy, or work, so ΔE = Efinal - Einitial < 0.
In letter <em>b</em>, the system is falling from a certain high to the floor, so its gravitational potential energy is change. That potential energy represents the energy that gravity does when an object shifts vertically. Because it goes from a high to 0, the energy is been lost, so ΔE = Efinal - Einitial < 0.
In letter <em>c</em>, the system is going higher and with higher velocity, so there is a greatness in the gravitational potential energy and the kinetic energy, both works, so ΔE = Efinal - Einitial > 0.
The equilibria showing how the acetate buffer adjusts to addition of a small amount of NaOH is:
- CH3COOH(aq) + H2O(1) → H30+ (aq) + CH3COO (aq)
<h3>What is a buffer?</h3>
A buffer is a solution which resists changes to its pH when small amounts of strong base or acid is added to it.
Buffers are made from solutions of weak acids and their salts or weak bases and their salts.
The equilibria showing how a buffer made from acetic acid and sodium acetate (NaCH3COO) adjusts to addition of a small amount of NaOH is as follows:
- CH3COOH(aq) + H2O(1) → H30+ (aq) + CH3COO (aq)
Addition of NaOH, a strong base will neutralize the hydronium ion, causing the acetic acid ionization equilibrium to shift to the right to produce more of the acetate ion, the conjugate base.
Learn more about acetate buffer at: brainly.com/question/17490438
