CMB1004/L19 Thermodynamics I

Question 1

What is osmolarity?

Answer 1

Number of molecules/ions per unit volume

Question 2

What occurs when a cell is placed in a hypertonic solution?

Answer 2

Crenation

Question 3

What occurs when a cell is placed in a hypotonic solution?

Answer 3

Swelling/lysis

Question 4

What does thermodynamics tell us about a reaction? (2)

Answer 4

Whether a reaction can be used as energy currency to make other things happen
Whether a cell needs to do work to make a reaction happen

Question 5

What is internal energy (U)?

Answer 5

The capacity of a system to do work

Question 6

Give 3 examples of energy stores.

Answer 6

Chemical potential energy
Kinetic energy
Thermal energy

Question 7

What is the first law of thermodynamics?

Answer 7

Delta(U) = w + q
Change in internal energy of a system = energy transfer by work + energy transfer by heat

Question 8

What is the equation for enthalpy change?

Answer 8

Delta(H) = delta(U) + pDelta(V)

Question 9

Why is Delta(H) always measured instead of Delta(U)?

Answer 9

Enthalpy is a much easier to measure version of internal energy

Question 10

What is entropy?

Answer 10

A measure of how disordered a system is

Question 11

What is the 2nd law of thermodynamics?

Answer 11

The entropy, S, of an isolated system will increase or remain the same