Week 1-How can we separate different types of solids? (Copy)

Before we begin this topic, we must understand what a mixture of different materials is. A mixture is when we have 2 more more different materials which are put together but do not react with each other to make new substances. This means that we can separate them and they will still be the same materials as they started off, even if they look slightly different. For example, pasta and water.

Please watch the video below to develop your understanding of mixtures.

Sieving is a method of separating dry solid particles of different sizes. The size of the particles which will be separated is controlled by the size of the holes in the sieve. Only the particles which are smaller than the holes in the sieve will go through and the larger particles remain caught in the sieve itself. We can also use sieving to separate a solid from a liquid. We often do this when we are cooking to drain boiled foods.

Please watch the video below for more information.

Optional task: We use sieves in the garden to separate stones from soil. We often use them in cooking too. With the permission of an adult, you could have a go at sieving soil or a mixture of foods.

This is a picture of a sieving machine. It separates mixtures which have different particle sizes all in one go. Each layer contains mesh with a different size of hole. The layers are arranged so that the largest holes are at the top and separate the biggest particles, the medium sized mesh is next, separating the medium sized particles and then the smallest particles drop into the bottom section for collection.

Task: Your task is to design, draw, colour and label a cross-section of an imaginary sieving machine. Please include a description of how it works. It needs to be able to separate 3 different sized solid particles. You can choose which particles you use. In the past some children have chosen different sized sweets (e.g.marshmallows, skittles, millions) or sport balls (e.g.basket ball, tennis ball, golf ball) but you can choose what you like. Really try hard with your drawing and labelling please. Then send it to me in Teams in the assignment in the science section. I have put some examples in the gallery below for you to look at so that you can see some examples.