Question

I have to make a project for chemistry for the given topic "Determination of Boiling point of 1 M sugar,urea, glucose, Bacl2 and Nacl2" consisting the following points:-
1)Aim
2) objective
3) introduction
4) methodology- requirements, chemicals, apparatus.
5) procedure
6) conclusion
7) result

Answer 1

Introduction:

The boiling point of a compound is the temperature at which it changes from a liquid to a gas. This is a physical property often used to identify substances or to check the purity of the compound.
It is difficult, though, to find a boiling point. Usually, chemists can only obtain a boiling range of a 2 - 3oC accuracy. This is usually sufficient for most uses of the boiling point.


Purpose:

The purpose of this experiment is to determine the boiling points of various organic compounds and to use these to identify unknowns.


Equipment / Materials:

hot plate
closed end capillary tube
thermometer
liquid organic compounds
250 mL beaker
small test tube


Safety:

symbol 183 \f "Symbol" \s 10 \h Always wear safety glasses in the lab.

symbol 183 \f "Symbol" \s 10 \h Capillary tubes break very easily, handle them with caution.

symbol 183 \f "Symbol" \s 10 \h Be careful with the thermometer. Mercury is very toxic.


Procedure:

1. Place a few milliliters of a known liquid organic compound in a small test tube.

2. Into the test tube, place the capillary tube with closed end upward.

3. Clamp the test tube to a ring stand and immerse a thermometer in the test tube. Be
sure to clamp the thermometer to the ring stand as well.

4. Fill a 250 mL beaker 3/4 full with water and place on the hot plate. Carefully lower
lower the test tube and thermometer combination into the beaker of water so that the
test tube is immersed half way in the water.

5. Begin to heat the hot plate/water slowly. As the liquid approaches its boiling point, a
few bubbles will be observed flowing out of the end of the capillary tube. When a
steady steam of bubbles are observed, turn off the hot plate and allow the contents of
the test tube to cool.

6. As the contents of the test tube cools, observe the capillary tube carefully. When
the liquid begins to flow into the capillary tube, record the temperature of the liquid
as its boiling point temperature.

7. Obtain an unknown liquid and repeat steps 1-6.


Substance
Boiling point ((C)
acetone
56-57
methanol
65
ethanol
78-79
propanol
97-98
2-propanol
82-83
Name_______________________________
Name_______________________________
Period______________________________
Date________________________________

Determination of Boiling Points

Data Table:

Practice Compounds:

compound

boiling range

- oC
compound

boiling range

- oC


Unknown:

compound

Unknown # ___________
boiling range

- oC
identity of substance



Questions:

1. What is the definition of boiling?


2. How is boiling affected by pressure?


3. How would the boiling point of a liquid change by:
a) measuring it in Denver (altitude - 5000 ft.)?


b) placing the liquid in a pressure cooker?