Question

1. What do volumetric glassware measure? What types of volumetric glassware will you be using in this experiment?

2. What is density? How is it calculated?

3.Define meniscus. State how you use the meniscus in making volumetric measurements. Draw a sketch of a meniscus for water in a graduated cylinder.

4. Define accuracy and precision. Explain what the “reliability of a measurement” means. (These concepts can be found in Chapter 1 of your text.)

5. Why will you calculate accurate volumes using density values and electronic mass measurements? That is, why can’t you believe that all volume measurements are perfectly 10. mL or 15 mL or 20. mL or 25 mL each, regardless of the volumetric device used?

6. Differentiate between systematic error and random error. (Also in Chapter 1 of your text.) Experimentally, how might you deal with each type of error to gather the most accurate and precise data possible?

7. How will you decide which type of glassware is most accurate? most precise?

8.How will you use density to calculate the volume of the water-alcohol mixture? Use equations to explain.

9.What does it mean when we ask: “Are the volumes of pure substances additive?”

Answer 1

Volumetric flask is a laboratory flask previously calibrated
.It help us to prepare accurate volume at particula temperature
which is known as standard solutions.These flasks comes
under different sizes which can contain 1mL to 20L of solution.

2.Density measures how much matter present in paritcular vulume.
More the matter in paricular volume more the density
less matter in same volume less the densty
Density can be calculated by follwing formula
density= mass/voume

3.when water kept in a graduated cylinder we can see the surface of
water is not straight but has a curved shape.tThis curved surface is
called meniscus.
It can be downward or upward depending on the liquid taken.
We will take the value of bottom line for upward meniscus
and upper line for downward meniscus.

4 Accurcy- IIt is the classness of a calculated value to
a standard value. For eg length of an object measuerd is
4.5mm whose actual length is 5mm means value is less accurate

precision- It is the clossness of two or more calculated values

reliability - It is the quality of measurement