8/13/2019 Catalyst+Nanoparticle+Shapes+ +Student+Instructions

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Context > Nanoscience > Teaching and Learning Approaches > Catalystnanoparticle shapes

Student activity Catalyst nanoparticle shapes

Students construct different shapes (sphere, cube, cylinder) using modelling clay, and calculate

surface area:volume ratios, to understand how shape and size affects activity of nanoparticles ascatalysts.

Activity idea

In this activity, students use modelling clay to construct different shapes (sphere, cube, cylinder)and calculate surface area:volume ratios with the aim of trying to develop a more efficient shape.

When developing nanoparticles as catalysts, their shape is very important. or a certain volumeof material, nanoparticles ma!e the best catalysts when they have a large surface area. "hismeans that plenty of atoms are available to help the reaction along.

When developing a new shape, students will need to measure or estimate its surface area. #nee$ample might be a tube % with an inside surface as well as an outside one, this will have a muchlarger surface area than a cylinder.

"he activity is suitable for students to wor! individually or in pairs. &ou may li!e to reviewcatalysts with your students before doing this activity.

Instructions

'ydrogen could be the fuel of the future. It is already used in fuel cells for cars and other vehicles.#btaining hydrogen from water, and using hydrogen to create electricity, are processes that needcatalysts to ma!e them efficient. any materials become catalysts when they are in the form ofnanoparticles, but the shape of the particles is very important. s many atoms as possible areneeded to ta!e part in the reactions.

"he best materials are very e$pensive (much more e$pensive than gold), so your challenge as achemical engineer is to find a shape that has the largest surface area for its volume. &ou will dothis using models and maths.

What you will need

plasticine or similar modelling clay % a ball about *+ mm across

ruler

callipers (useful for measuring spheres, but not essential)

calculator

piece of ba!ing paper or similar to wor! on

InstructionsWor!ing with a piece of modelling clay, you are going to change its shape and measure thesurface area each time. "he volume must stay the same, so do not remove or add any claybetween measurements.

efore you start, ma!e a prediction: Which shape will have the largest surface area: a sphere, acube or a cylinder-

. /oll the clay into a ball. a!e it as near a regular sphere as you can.

The Science Learning Hubwww.sciencelearn.org.nz

8/13/2019 Catalyst+Nanoparticle+Shapes+ +Student+Instructions

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Context > Nanoscience > Teaching and Learning Approaches > Catalystnanoparticle shapes

0. easure the diameter of the ball, and record it in the table below.*. a!e the clay into a cube, as regular as you can.1. easure the length of each side (they should all be the same) and record it in the table

below.2. /oll the clay into a cylinder3. easure the diameter and length, and record it in the table below.

Shape 4iameter (mm) /adius (mm) 5ength (mm) Width (mm)

Sphere

6ube

6ylinder

7. 6alculate the volumes and surface areas and record your answers in the table below.ecause you used the same piece of clay each time, the volume should be about thesame. Include it in your calculations to ma!e sure.

Calculations:

Sphere

8olume 9 1* $ $ (radius)*

ultiply the radius by itself twice (e.g. *$*$*).

ultiply that number by *.1 (an appro$imation of pi).

ultiply that number by 1.

4ivide that number by *.

Surface area 9 1 $ $ (radius)0

ultiply the radius by itself once (e.g. *$*).

ultiply that number by *.1 (an appro$imation of pi).

ultiply that number by 1.

Cube8olume 9 length $ width $ height

ultiply the length by the width.

ultiply that number by the height,

Surface area 9 length $ width $ number of sides

ind the area of one side and multiply by 3.

Cylinder

8olume 9 height $ $ (radius)0

ultiply the radius of the end circle by itself once (e.g. *$*).

ultiply that number by *.1 (an appro$imation of pi). ultiply that number by the height of the cylinder.

Surface area 9 0(radius)0; 0$ radius $ height

a) ultiply the radius of the end circle by 3.0< (which is 0 pi).b) ultiply that number by the height.c) ultiply the radius of the end circle by itself once (e.g. *$*).d) ultiply that number by 3.0

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