Sticky water
-
Upload
limguanhuat -
Category
Documents
-
view
469 -
download
1
Transcript of Sticky water
Sticky Water
By Lim Hur (20)5L
Gravity
Gravity pulling water down
Water defying gravity
What makes water so sticky?
Adhesion keeps the water stuck to the stringCohesion keeps the water stuck to itselfTogether, these two forces keep the water
flowing in a stream stuck to the string
Stick to itself force=cohesion
Stick to other things force=adhesion
Cohesion
Negative Charge
Positive Charge
Water Molecule
Hydrogen Bonding
Adhesion
Negative Charge
Positive Charge
Water Molecule
What if…
A) I use strings of 60cm and 90cm length for the experiment?
Experimental Procedures A) 1. Fill the pitcher half full with water. Add a few
drops of food colouring to make it more visible as it moves down the string.
2. Soak a length of 60cm and 90cm cotton string in water thoroughly.
3. Tie one end to the pitcher and stretch it tightly across the pouring spout.
4. With one hand, hold the pitcher by the handle about 30cm above and 60cm or 90cm away from the pitcher. Hold the string against the inside of the glass with the other hand.
5. Slowly pour the water down the string.
60cm distance between pitcher and glass
MVI_8306_FIX.MPG
90cm distance between pitcher and glass
What if…
B) What if I use strings of the same length, but have different diameters of 10mm and 18mm for the experiment?
Experimental Procedures
B) Repeat the steps in (A), this time using strings of 10mm and 18mm diameter instead.
String of
10mm diameter
String of
18mm diameter
Table of resultsString used to connect pitcher
to glass
If the water flowed from the pitcher to the glass
1st attempt
2nd
attempt3rd
attempt
Yes Yes Yes
Yes Yes Yes
Yes Yes Yes
Yes Yes Yes
String used to connect pitcher to
glassString of 60cm length
String of 90cm length
String of 10mm diameter
String of 18mm diameter
ConclusionCohesive forces are apparent between like
molecules. For instance, once the string is wet in
the experiment, the water can cling to the
already present water molecules and slide down
the string to the glass.
Likewise, adhesive forces are present in this
experiment. The water molecules are attracted
to the string molecules.
Hence, cohesion and adhesion can work together
in different length or thickness of string.
THEEND
Q & A