The Meniscus

	Normally, liquid will curve at the edges of the surface where the liquid touches the container because water molecules are more attracted to glass than to each other.  This curvature is called the meniscus. We need to read the level at the bottom of the meniscus to measure a volume of liquid in a graduated cylinder.
	There are some materials where the curve goes up. In this case, we read the top of the meniscus.
	In some plastic cylinders water has a flat surface. In that case, we use the centre rather than the edges.
	The visibility of the meniscus can be enhanced by using a card with a dark stripe and placed behind the cylinder.  Then, adjust the placement of the card to give us either a white meniscus against a black background or a black meniscus against a white background.
	We need to read the meniscus at eye level in order to get an accurate reading and if we see the liquid slightly above or below, we may find a little shift in the meniscus and get inaccurate readings. We should place the graduated cylinder on the table and then lower their heads to be able to read the meniscus at eye level.

	Videos on how to measure volume using graduated cylinder at http://www.youtube.com/watch?v=iPkZlce84ag
	Additional explanation and some exercise on measuring volume using graduated cylinder at http://www.wisc-online.com/objects/ViewObject.aspx?ID=gch302

Liquids Volume Measurements in Graduated Cylinders

Graduated cylinder is one of measurement tools to measure volume of liquids. The accuracy of the measurement depends on the size and type of graduated cylinder being used. It come in various sizes including 10ml, 25ml, 50ml, 100ml, 500ml and 1000ml.

Different kinds of graduated cylinders are set up differently. Hence, each line or interval on the graduated cylinder may represent different value. The volume increment for each of those lines will be determined by the divisions between consecutive numbers. For example, a usual 10 millilitre cylinder has 10 divisions from one number to the next; therefore, the volume increment for each of those lines is a tenth of a millilitre.

Attribute for Volume of Liquids

Definition of Volume of Liquid

 Volume is the measure of how much space an object takes or the amount of space taken up by a three-dimensional object. Volume of liquid refers to the capacity of liquids in the containers or refers to a quantity of liquid or the amount of space taken up by a liquid that absolutely spreads to fill its storage place. The volume of a container is generally understood to be the capacity of the container, i.e. the amount of fluid (gas or liquid) that the container could hold, rather than the amount of space the container itself displaces.

Capacity can be measured by using non standard units (more or less) and in standard units in the metric system. The Metric System Units for measuring volume are millilitres and litres. Millilitres are used to measure a small liquid volume, such as a dosage of cough medicine and heavy cream. The volume of a bigger amount, like a bottle of mineral water, an aquarium or swimming pool can be measured using litres.

There are numerous tools used for measuring volume such as:

 

1)       Measuring spoons
2)       Measuring cups
3)       Burette
4)       Graduated Cylinders
5)       Beakers

	Videos on how to measure capacity at http://www.youtube.com/watch?feature=player_embedded&v=ih-Jny73DUg
	Students can enhance their understanding on this topic by playing games at http://pbskids.org/cyberchase/games/liquidvolume/liquidvolume.html