Measuring Mass and Volume in the science classroom Objectives: Learn three different ways to measure volume and the tools used Learn to find mass and the tools used Learn vocabulary associated with measuring mass and volume

Mass We use a TBB We label it grams What is mass? The amount of matter in an object. The matter in our case is atoms.

A triple-beam balance gets its name because it has three beams that allow you to move “riders” along the beams.

Using the TBB Be sure the pan is clean and the weights are on the zero- balanced Move the 100 gram slider along the beam to the right until the arrow drops below the fixed mark. Be sure the weight is into the notch. Now move the 10 gram slider along the beam to the right until the indicator drops below the fixed mark. This also must be in the notch. The beam in front is not notched; the slider can move anywhere along the beam. The boldface numbers on this beam are grams and the tick marks between the boldface numbers indicate tenths of grams. To find the mass of the object on the pan, simple add the numbers from the three beams.

Think about it… Mass is not the same as size - some big things, like balloons, are very light, while some small things, like a lead bullet, are very heavy. A truck would be the same size whether it was empty or full, but it would have a lot more mass if it was full but still same size - and it would be even harder to stop

Volume ...Volume is the amount of space that an object takes up X X

Measuring the volume Of a liquid... We use a graduated cylinder We label the units mL (milliliters) Then we have an “irregular” solid (we’ll talk about this later)

Let’s look at the liquid! It is important to notice what each line or interval on the graduated cylinder represents. Different kinds of graduated cylinders are set up differently.

The Meniscus A characteristic of liquids in glass containers is that they curve at the edges. This curve is called the meniscus. You measure the level at the lowest part of the meniscus. With water in glass, the meniscus will curve up at the edges and down in the center so we say you read the bottom of the meniscus.

So how do you do find the volume of a liquid? Finding the volume of a liquid is easy, for all you need to do is pour the liquid into a graduated cylinder and that's its volume. Label it mL.

Now a “regular” solid Use a ruler to measure the volume of a solid (all sides are even and can be easily measured): Use the formula Length x Width X Height. It doesn't matter what you consider your length, width, or height as long as you don't measure the SAME SIDE TWICE. Label cm³

Lastly...the “irregular” solid An irregular solid is one that does not have even sides to measure, like a prism, and it is not a liquid that can pour. This is why we use.. Water Displacement (displacement means movement) Water displacement is a method of measuring an object's volume. If you: Measure a quantity of water in a graduated cylinder (be sure water covers object) Then place an object in the cylinder. Subtract the original amount from the new amount. Your total will be the volume of the object. (label it cm³)

Measurement… Can you name three ways to measure volume? What tool do you use to measure mass? What is the name of the lowest level curved edge that we read the water level in a graduated cylinder? What is the method called that we use to find the volume of an irregular object?