Name: 如何點燃本生燈 (How to Light a Bunsen Burner)
Uploaded: 2021-01-14T06:44:43.000Z
Duration: 4 min 11 s
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情態副詞

how to use a bunsen burner saftly and properly.

It allows you to heat materials in the lab

both quickly and efficiantly. Because you will be working with an open flame

it can be dangerous, so I will start by going over some safety rules.

All long hair should be tied back and you should not wear any loose or bulky clothing.

You should never heat inflammable materials on the bunsen burner.

Volatile and inflammable materials like ethers and alcohols can combust in heat, so it is defiantly to dangerous for the bunsen burner .

When handling the barrel of the bunsen burner it is important

When the flame is lit it can get very hot

You should never leave  your bunsen burner unattended  when it is lit.

where all emergency exit and emergency gas shut offs are as well as all safety equipment before you start using your bunsen burner.

Now that you know all the safety percautions you can begin to light your bunsen burner.

The first step is to attach the hose to both the bunsen burner and the gas line.

Make sure that you attach it to the gas line and not an air or water line.

You will now want to turn the barrel clock wise

to completely close the air inlet, do this until there is resistance.

Now turn it back slightly so that just a small amount of air is let through

You will also want to close the gas needle valve located underneath the bunsen burner.

Leave this closed for now and turn on the gas

You will know the gas tap is open when the

You will now want to turn the gas needle valve clockwise slightly to open it.

This lets a small amount of gas through you should be able to hear faint hissing

which lets you know that the gas is coming out of the burner.

and generate sparks over your bunsen burner.

You may want to practice this a few times just before you turn the gas on

like I am doing. To do this you want to push up and across

Hold the flame just above the bunsen burner and generate the sparks.

You should now have a flame that is yellow and orange colour.

To get a taller flame turn the gas needle valve clockwise.

and likewise to get a shorter flame turn it counter clockwise.

and  like wise to get a short flame turn it counter clockwise.

Once you have your flame at a sufficient height you will want to adjust the heat to make a

hotter flame you will want to turn the barrel, do this by holding it at the

base. To increase the heat you will want to turn the barrel counter clockwise.

This should change the colour of your flame from yellow-orange to blue.

Be careful when handling the barrel at this point because it can get very hot

You will also want to make sure not to let too much air in because this can blow

out your flame. You will know your flame is ready to use when

it is dark blue in colour with a darker inner core.

You will want to hold your item just above the inner core to be in the hottest location.

When you  have finished using the bunsen burner there is a correct proceedure for turning it off safely.

First you will want to turn your flame back to yellow

by letting more air in.  Do this by turning the barrel, holding the bottom, in the clockwise direction

now you will want to turn your gas needle valve off by turning it counter clockwise.

Lastly, turn off the gas tap. You have now finished

turning off your bunsen burner, but make sure to let it cool

Using a bunsen burner can be intimidating to even some of the most experienced chemists

but if you follow the instructions and safety protocols that I have taught you,

you can always make sure that you proceed with the utmost