CLOUD CHAMBER & FOG FORMATION

jeanscricketInternet and Web Development

Nov 3, 2013 (3 years and 10 months ago)

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CLOUD CHAMBER
& FOG FORMATION

MATERIALS



1 clear glass or plastic jar w/ wide mouth



1 rubber glove (
Latex)




Matches



Water



Ice (Crushed)

PROCEDURE

EXPERIMENT #1

1.

Barely cover the bottom of the gallon jar with water

2.

Hang the rubber glove inside the jar wi
th the fingers down, and stretch
the open end of the glove over the mouth of the jar for a tight seal.

3.

Insert your hand into the glove and pull it outward without disturbing the
seal of the jar.

4.

Nothing should happen.

EXPERIMENT #2

1.

Remove the glove, dr
op two to three lit matches into the jar, and
replace the glove for a tight seal.

2.

Pull outward on the glove once more.

3.

Fog should form inside the jar when you pull outward with the glove.
The fog will disappear when the glove is snapped back.

EXPERIMENT

#3

1.

Remove the glove, drop two to three lit matches into the jar, and
replace the glove for a tight seal.

2.

Pull outward on the glove once more.

3.

Allow glove to snap back and add crushed ice. Fog will form at the tips
of the fingers.


QUESTIONS

1.

What is hap
pening to the pressure inside the jar when the glove is
pulled outward and when the glove snapped back?

2.

Why was there no smoke in the first part on the experiment?

3.

What is the purpose of the matches in the second part of the
experiment?





RATIONALE

W
ater molecules in the form of invisible water
vapou
r are present
inside the jar. This water
vapou
r is quickly moving around inside of the jar
without sticking to each other. When the glove is pulled outward the air is
expanding inside of the jar and therma
l energy is lost. This causes the tiny
water molecules to slow down and stick to each other. These water molecules
bunch together more easily when there are solid particles to act as a nucleus,
such as smoke, dust or other particles in the air.

When the gl
ove is pushed back into the jar the pressure is increased
and the air is warmed causing the tiny droplets to evaporate.

In the atmosphere, air expands and releases heat as it rises to regions
of lower pressure. As heat is lost, the air cools and condenses

on dust and
smoke particles which provide nuclei to help the water condense.

Meteorologists conside
r a falling barometer

(low pressure) to be a sign of
approaching storms, while a rising barometer (high pressure) is a sign of clear
weather. The temperatu
re at which the water droplets begin to form is called
the dew point.

How are clouds formed?


Air contains moisture in the form of a gas which is called
water vapour
. As
water vapour cools it changes from a gas into a liquid. Clouds form when
water vapou
r in the air cools and changes into droplets of water. The tiny
water droplets gather together to make a cloud.

Types of Clouds

.

The three main kinds of clouds are
cirrus, stratus,
and

cumulus
.


Cirrus

clouds are white and feathery, and form high up in
the sky.
They are wispy and thin.



Stratus

clouds are like flat grey sheets layered across the sky.
They are the lowest clouds in the sky, and the drops of water
vapour in them are very small. The rain that falls from stratus
clouds is drizzle, or snow i
n very cold areas.



Cumulus

clouds are thick and fluffy, and change shape
rapidly.They can be white or dark when they are full of water
droplets and very cold.



All other clouds are combinations of these three. There are ten types of
clouds that are fo
und at different levels of the atmosphere

Rain clouds have '
nimbo
' or '
nimbus
' as part of their name. For example,
cumulonimbus

are fluffy clouds that bring rain and thunderstorms. They
have large drops of rain, and as the temperature gets colder, the drop
s of
rain join together and the cloud becomes dark. They bring lightning,
thunder or hail.
Nimbostratus

are layers of rain cloud.

The highest of all the clouds are the group of clouds with '
cirrus
' as part of
their name. They are feathery and white and are

made up of frozen water
droplets. Adding '
alto
' to the name of a cloud tells that it is a cloud high in the
sky.


Some websites that are good for this area of study include:

http://www.bom.gov.
au/info/clouds/

http://www.weatherwizkids.com/

http://www.dailymotion.com/video/x9ybdn_our
-
world
-
cool
-
clouds_tech?f
rom=rss

http://www.youtube.com/watch?v=msSVQ903T8k

excellent video that uses a
foot pump and rubbing alcohol in place of water and smoke.


APPLICATION

This activity can be used for VELS level 5,

Solid/Liquids & Gasses as it is
looking at the evaporation and condensation of water molecules that form the

fog

. You could also use this activity for VELS level 6 in the area of Global
atmospheric changes, c
hanging weather patterns, falling and rising
barometer, relation of temperature and pressure.




MAKE YOUR OWN BAROMETER I


MATERIALS:



small coffee can



plastic wrap



scissors



straw



index card



rubber ban
d

PROCESS:

1.

Tightly cover the top of the coffee can with plastic wrap, using a rubber
band to hold the plastic wrap in place. The cover should be tight
making the can airtight.

2.

Place the straw horizontally or sideways on the plastic wrap so that
two
-
third
s of the straw is on the can.

3.

Tape the straw to the middle of the plastic wrap so that it will not fall off.

4.

Tape an index card to the can behind the straw. The straw will act as a
pointer on the card.

5.

Carefully record the location of the straw on the i
ndex card with a
pencil. If desired, marks can be drawn on the index card to make
observing the changes easier.

6.

After 15 minutes, record the new location of the straw on the index
card. Continue checking and recording the straw location as often as
you wa
nt.


EXPLANATION:

High pressure will make the plastic cave in and the straw go up. Low pressure
will make the plastic puff up and the straw go down. If possible, check your
measurements with a real barometer.