Presented by : Aye Swe Lwin Su Chang Nicole Tan Michelle Lim Tang Hui Shi Geraldine Chan Charmaine Lee Kiona Chong Class M07107 NUS High School

What is viscosity? -Introducing Viscosity Experiment and procedure on testing which liquid is more viscous. What affects Viscosity? – Brief explanation on a factor that affects viscosity. An exceptional liquid. Whee! I’m gonna LEARN!

What is density - Introducing density Experiment of density of liquids. An activity based on density - Cocktail making. :D

When I say Viscosity is … You say The measure of resistance towards fluid Learn This!

-Viscosity is the "thickness" or the resistance towards flow. -For example, ~ Apple Juice is “thinner” than honey, so apple juice has a lower viscosity than honey. ~ Ketchup is “thicker” than water, so ketchup has a higher viscosity than water.

Now, YOU name a few examples of which liquid is “thicker” or “thinner” than which liquid! Is it more or less viscous?

  All liquids have viscosity.  Different liquids have different levels of viscosity. How can you tell?

Experiment  Purpose: Find out which liquid is the most viscous.  Materials: ~ 4 different liquids. ~ 4 marbles of the same size ~ 4 measuring cylinders ~ 1 stopwatch Summary:  You will time how long each marble takes to reach the bottom of the measuring cylinder, with the same amount of different liquid in each cylinder.  The longer the time taken for the marble to reach the bottom of the cylinder, the more viscous the liquid is.

1. Pour 80ml of each liquid into separate measuring cylinders. 2. Have one person to be in charge of timing, while another person in charge of dropping the marble. 3. Start timing with the stopwatch once you drop a marble into the first cylinder. *Note that you gently drop the marble and not throw it in. 4. Stop timing as soon as the marble reaches the bottom of the cylinder. 5. Repeat your experiment 2 times for each and every measuring cylinder to reduce any errors made.

Now that you know different liquids have different viscosities, we will now find out what affects viscosity. One of them is temperature.

When the liquid is being heated up, the liquid “melts” and gets thinner. Hence, it become less viscous. Graph for better understanding… Original Liquid Become a liquid which is thinner and less viscous.

Although temperature changes the viscosity of the liquid, there is one that does not have its viscosity changed even if the temperature changes. What is it? Prize is awarded for the correct answer!

Hello!

Now, we have finished learning viscosity, let’s do some recap on the 6 main points that we have learnt. 1)Viscosity is the measure of thickness of a fluid. 2)Which is also the resistance towards flow. 3)All liquids have viscosity 4)Different liquids have different levels viscosities. 5)Temperature affects the viscosity of the liquids 6)Water is one liquid that does not have its viscosity changed even if its temperature changes.

Just joking…. We will be moving onto….

Now, we are going onto density. With the liquids we had used for the viscosity experiment just now, we will be doing another experiment on density. So, that’s the link between these two different topics.

Density is the measure of the amount of particles per unit volume. Things with more particles per unit volume have a higher density. What does this mean? Let’ see… One = One unit volume One = One particle

Different liquids have different densities. Liquids with higher density will be below the liquids with lower density when they are poured into one container.

Experiment Purpose: To find out which liquid has a higher density. Material: ~ 3 cylinders. ~ 2 different liquids that does not dissolve in each other. (Oil & Water) Summary -You will pour the liquids into the cylinder one by one with the same amount and after a few minutes, you will see which liquid is on top of which liquid. - The liquid at the bottom most is the density will the highest density.

1)Prepare 50ml of oil and 50ml of water in two separate cylinders. 2)Pour the oil and water into the another empty cylinder one by one. 3)Wait for 30 seconds. 4)What has happened? Record your observations. Result of the experiment The oil and water separates into two layers. Oil is “on top” of water.

This is because water has a density than oil. Which means, water has more particles per unit volume than oil. So, water with more particles will sink to the bottom

Now, you have finish learning about viscosity and density of liquids. So, we will do a fun activity to

That is… Material: ~two big jugs ~one cocktail shaker Ingredients: 2 oz freshly pressed apple juice (green or gold apples) 1/2 oz simple syrup 1/4 oz lemon juice granulated sugar for rimming apple slice for garnish

Add apple juice, simple syrup and lemon juice to a cocktail shaker filled with ice. Shake well. Strain into one of the chilled glass jug rimmed with granulated sugar. Garnish with an apple slice. Done!

The drinks are separated into 4 layers. This means that the 4 drinks have Another result:

That marks the end of our presentation, and, enjoy your cocktail! =D

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Done by: Aye Swe Lwin, Su Chang, Nicole Tan, Michelle Lim, Kiona Chong, Tang Hui Shi, Geraldine Chan, Charmaine Lee Class M07107 NUS High School