Why do scientists use STP and standard units?

Question

I need at least two reasons for my chem lab report.

Answer 1

Standard Temperature and Pressure are absolutely necessary when you are working with gases. Gases expand and contract a tremendous amount depending on the temperature and pressure of the gas. The volume fluctuates so much that we cannot begin to compare them unless we convert them to standard conditions.

Any standard unit is based on a very specific amount. Imagine a world where there are no standard units of length. Think how difficult it would be to go to the lumber yard to buy wood for a project you are completing. What would clothes sizes be like with no standards? How would you know which gas station has the best price if they did not use standard units?

Answer 2

Science has to be consistent and all measurements must be consistent. That is why measurements have been standardized for use by scientists all around the world, and that's also why we have to use the metric system in chemistry class! And they use standard temperature and pressure so that they can consistently make measurements for different substances, and be able to compare them. Basically, it's all about consistancy.