2021 BSN Bunsen-Burner-Lab PDF

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Summary

about parts and descriptions about bunsen burner...

Description

Experiment No. 5 The Bunsen Burner Part 1: Parts of a Bunsen Burner Parts of the Bunsen Burner Watch a video showing the different parts of a bunsen burner as found in this drawing.

A. Barrel - Where gas and air are mixed B. Collar - To adjust the air intake C. Air intake openings (air holes) - Air enters here D. Gas Flow Valve - Regulates flow of gas (can also be controlled from table gas valve)

E. Gas intake tube – Gas enters burner from table source. F. Base - Supports burner In your worksheet;

1. Sketch one of the Bunsen burners from the lab. 2. Identify and label its parts using the guide sheet! 3. Give the purpose of each part of the Bunsen Burner! 4. What parts of the Bunsen burner allow air to be mixed in with the gas? Why do the gas and air need to be mixed .

Part 2: Setting Up a Bunsen Burner (View the video link) How to Light a Bunsen Burner: https://youtu.be/N7ssCM3qM3U Procedure: 1. Connect the hose to the gas main outlet. Clear the area of all flammable objects (avoid very loose sleeves/ clothing & tie your long hair!) 2. Make sure that the air intake openings are closed. 3. Close the gas flow valve at the bottom of the burner, 4. Light a match on the top of the barrel. Slowly open the gas valve at the base of the burner. Note that the flame is yellow and that the flame brightens the room.

The following chemical reaction occurs with the air holes are closed.

INCOMPLETE OXIDATION or Incomplete Combustion is a reaction occurs when there is insufficient supply of oxygen ( in this experiment, the airholes are closed) : https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.sciencephoto.com%2Fmedia%2F4991%2Fview%2Fgasflame-of-a-bunsen-

j

burner&psig=AOvVaw3HboV2zYBmZTxLbe46HAgO&ust=1629943242958000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCNi7_fGJy_ICFQAAAAAdAAAAABA

Chemical Reaction occurring in the flame with limited supply of Oxygen: C3H8 + 3.5 O2 → CO2 + CO + C

+ 4 H2O + heat +light

Propane + Oxygen → Carbon Dioxide + Carbon Monoxide + Carbon (soot) + Water + heat energy + light energy 5. Adjust the barrel so that the flame is pale blue with a dark blue inner cone.

https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.sciencephoto.com%2Fmedia%2F428107%2Fview%2Fbunsen-burner-flamesequence&psig=AOvVaw3HboV2zYBmZTxLbe46HAgO&ust=1629943242958000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCNi7_fGJy_ICFQAAAAAdAAAAABA0

The following chemical reaction occurs when the air holes are opened. Combustion is an exothermic reaction that releases energy in the forms of heat and light. COMPLETE OXIDATION/COMBUSTION : Chemical Reaction occurring in the flame: C3H8

+ 5 O2

→

3 CO2

+

4 H2O + heat

Propane + Oxygen → Carbon Dioxide + Water + heat

When a fuel undergoes complete combustion, it releases the maximum amount of energy from the fuel being reacted. Complete combustion is usually characterized by a blue flame.

Parts of the non luminous Flame

2 3

Incomplete combustion is often undesirable because it releases less heat energy but more light energy than complete combustion and produces carbon dioxide and carbon monoxide and Carbon soot. Incomplete combustion can also produce pure carbon (soot). Incomplete combustion is characterized by an orange coloured flame.

In your worksheet; copy the drawing below; Label the Positions A to D which is the hottest or coolest part of the flame. State the reason for the difference in temperatures.

Exercise No.5 The Bunsen Burner Name:

Course Year Section:

Date:

1. Sketch the Bunsen burners from the discussions. Identify and label its parts. Give the purpose of each part.

2. Why do the gas and air need to be mixed ? 3. Write the balanced Chemical reaction when there is enough oxygen to support combustion. Write the names of the reactants and products.

3a.What type of flame is produced, luminous or nonluminous? 4.Write the balanced Chemical reaction when there is NOT enough oxygen to support combustion. Write the names of the reactants and products.

5.What type of flame is produced in item 4, luminous or nonluminous? 6. Which flame( luminous or nonluminous)produced soot?

Draw a luminous flame as per instruction and label refer to instruction above.

5...