W3 PASS

DIFFUSION + TONICITY

W3 PASS

DIFFUSION + TONICITY

W3 PASS

DIFFUSION + TONICITY

W3 PASS

DIFFUSION + TONICITY

TODAY’S SESSION

FACT OR FISHY

Any concerns you want to cover in class?

TODAY’S SESSION

KAHOOT

Multi choice quiz :)

SAQs

• Table Groups

• Understand the concept of tonicity and osmolarity via diffusion
• Apply Fick’s law to real world situations
• Describe how diffusion applies in the human body

TEST pump up

Next week :3

1. MOODLE self-review tests
2. End of workshop multi choices
3. Youtube to revise theory (don’t rewatching lectures)
4. PASS practise test
5. Textbook questions
6. Know your formula sheet!

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W5 test

https://learning.monash.edu/mod/page/view.php?id=3308342

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two (2) A4 sheets with any notes you like on both sides

20 MCQs - 60 minutes to complete the test. ~3 mins per Q

1. FLAG AND MOVE THE F ON
2. Don’t be overwhelmed by the information presented. Always break it down into all the variables presented and what you need to find
1. This will allow you to figure out the required formula
2. Appropriate formula is sometimes the simplest

If there is mass and acceleration (F=ma)

• Pay attention to the units
• Pay attention to sig.figs
• Once finished double check your flagged questions

DURING THE TEST

TEST PREP

WIN OF THY WEEK

FACT OR FISHY

WIN OF THY WEEK

FACT OR FISHY

WIN OF THY WEEK

FACT OR FISHY

WIN OF THY WEEK

FACT OR FISHY

WIN OF THY WEEK

FACT OR FISHY

WIN OF THY WEEK

Memory hacks (tonicity)

=The biggest social climber that ever was

WIN OF THY WEEK

Memory hacks (solute vs solvent)

UTE gets stuck in the VENT

WIN OF THY WEEK

**ATTENTION TO (mole)

1 dozen party pies

= 12 party pies

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“Number of particles”

1 mol of something

= 6.02 x 10²³of something

WIN OF THY WEEK

SUMMARISED conversion

moles per second

KAHOOT time

molelele

A research student asked to make up a 2 litre solution of 5% m/V glucose in water.

1. What is the required mass of glucose in grams?
1. %m/V = 5% = mass of solute / volume of solution (mL)

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b) How many mol of glucose is required to 3 dp?

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c) What is the concentration of glucose in mol/L to 3 dp?

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W3 slides:

molemole

A research student asked to make up a 2 litre solution of 5% m/V glucose in water.

• What is the required mass of glucose in grams?
• %m/V = 5% = mass of solute / volume of solution (mL)

2L = 2000 mL

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x / 2000 = 5% (or we can say 0.05)

X = 0.05x2000

= 100 g

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b) How many mol of glucose is required to 3 dp?

100g of glucose

C6H12O6= 180.156g/mol

n(glucose) = 100/180.156

= 0.555 mol

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c) What is the concentration of glucose in mol/L to 3 dp?

c(glucose) = 0.555 mol / 2 L

= 0.278 mol/L

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W3 slides:

DR EVIL?!

1. Using the rms formula, how long do you have to find the unlock button to escape before the gas reaches you, rounded down to the nearest second?

Dr EVIL farts near you in a subway but his farts contain sarin gas. The diffusion coefficient (D) is 20 m²/s. If the gas reaches you, you will die by inhibition of acetylcholinesterase enzymes, leading to violent persistent muscular contractions that prevent breathing. You run to a maintenance door 50 m away that has been locked by mini me😱. Assume the time taken to run is negligible.

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DR EVIL?!

Dr EVIL farts near you in a subway but his farts contain sarin gas. The diffusion coefficient (D) is 20 m²/s. If the gas reaches you, you will die by inhibition of acetylcholinesterase enzymes, leading to violent persistent muscular contractions that prevent breathing. You run to a maintenance door 50 m away that is locked by mini me😱. Assume the time taken to run is negligible.

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• Using the rms formula, how long do you have to find the unlock button to escape before the gas reaches you, rounded down to the nearest second?

Xrms = 50m, D = 20m^2/s, t = ?

50m = sqrt(2 * 20 m^2/s * t)

t = 50^2 m^2 / (2 * 20m^2 * s^-1)

t = 2500m^2 / (40m^2 * s^-1)

t = 62 s

Special cell

The solute concentration inside a special cell is 100 mOsm (all non-penetrating) and the concentration of the extracellular fluid is 400 mOsm. The solute concentration of ECF is made up of 150 mOsm of glucose (large polar molecule) and 250 mOsm of O2.

1. Calculate the osmolarity and the tonicity of this cell.

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• Is water likely to move into or out of the cell?

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c) If oxygen has a diffusion constant of 100 x 10^-11 m2/s and travels 4nm, find how long it will take for oxygen to diffuse out of the cell.

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Special cell

The solute concentration inside a special cell is 100 mOsm (all non-penetrating) and the concentration of the extracellular fluid is 400 mOsm. The solute concentration of ECF is made up of 150 mOsm of glucose (large polar molecule) and 250 mOsm of O2.

• Calculate the osmolarity and the tonicity of this cell.

mOsm = milliosmole, osmol= mol/L

therefore mOsm → osmol= /1000

Osmolarity - all particles

ECF= 400mOsm = 0.4 osmol

ICF= 100mOsm = 0.1 osmol

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• Is water likely to move into or out of the cell?

ECF has increased tonicity because:

150mOsm of glucose > 100 mOsm of intracellular solute

=water will leave the cell

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c) If oxygen has a diffusion constant of 100 x 10^-11 m²/s and travels 4nm, find how long it will take for oxygen to diffuse out of the cell.

In its dissolved form, O₂ doesn’t dissociate into individual oxygen atoms. Instead, it stays intact as the molecule O₂, which is considered one particle.

4x10^-9=sqrt(2(100x10^-11)t)

t= (4x10^-9)² / 2(100x10^-11)

t= 8 x 10^-9

Tonicity - non-penetrating only

ECF= 150mOsm = 0.15 osmol

ICF= 100mOsm = 0.1 osmol

K

The diffusion coefficient for potassium ions crossing a biological membrane 10 nm thick is 1.0 x 10^–16 m²/s. What number of potassium ions would move per second across an area 100 nm by 100 nm, if the concentration difference across the membrane is 0.50 mol/L?

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K

The diffusion coefficient for potassium ions crossing a biological membrane 10 nm thick is 1.0 x 10^–16 m²/s. What number of potassium ions would move per second across an area 100 nm by 100 nm, if the concentration difference across the membrane is 0.50 mol/L?

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Δx= 10x10^-9

D= 1x10^-16

A= 100x10^-9 x 100x10^-9 = 1 x 10^-14 m²

C= 0.50 mol/L ⇒ mol/m³ x1000 = 500 mol/m³

(1 Litre is 0.001m³)

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Plug into ficks law and solve for J!!!

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OXYGEN IN A PIPE (ext question)

Oxygen gas is flowing through a 10m long circular pipe with a radius of 16cm. The concentrations of oxygen at the ends of the pipe are 30kg/m³ and 10 Kg/m³. The diffusion constant for O2 at 20C is 1.8x10^-5 m²/s.

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A) Calculate the diffusion flow rate

B) how many Kg of oxygen will flow through this pipe in 15 minutes?

C) Calculate the concentration gradient

D) what is the concentration of Oxygen 2m away from the end of the pipe at high concentration?

E) How long will it take 100kg of oxygen to travel through the pipe?

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OXYGEN IN A PIPE (ext question)

Oxygen gas is flowing through a 10m long circular pipe with a radius of 16cm. The concentrations of oxygen at the ends of the pipe are 30kg/m³ and 10 Kg/m³. The diffusion constant for O2 at 20C is 1.8x10^-5 m²/s.

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A) Calculate the diffusion flow rate =2.9x10^-6 kg/s

B) how many Kg of oxygen will flow through this pipe in 15 minutes?

=2.61x10^-3 kg

C) Calculate the concentration gradient =20 decrease kg/m³

D) what is the concentration of Oxygen 2m away from the end of the pipe at high concentration? = 26kg/m³

E) How long will it take 100kg of oxygen to travel through the pipe?

=399.1 days

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https://youtu.be/JgAKv1Zlgcw ← worked through solutions - recommend trying this application!!

See u next week !

Week 4= Gas laws

Good luck for your test during your LAB NEXT WEEK

PDF OF TEXTBOOK ON PASS DRIVE

Chapter 16: 16.1, 16.3, 16.4, 16.6, 16.7, 16.9, and 16.10.

Chapter 18: 18.2(a-c)

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