please help me to solve this activity
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Answ
Two identical small, wide-mouthed jars (baby food jars are perfect)
Hot water
Cold water
Food coloring
Index cards or squares of waxed paper
Scissors
A large, shallow baking pan (if you don't have one, do this activity in the sink--it can be messy)
Fill one of the jars with very hot tap water. Add a drop of red food coloring. What happens to the drop? Watch for a minute, then put the red jar into the baking pan.
Fill the other jar with cold water. Add a drop of blue food coloring. What happens to that drop?
Tips for Home Scientists
This experiment can be tricky--and messy. You may want to practice step 6. Get a grown-up to help.
Cut about 2 inches off one short side of the index card. You should end up with a square about 3 inches on a side.
Slowly add more water to the blue jar until you can see a bulge of water over the rim of the jar.
This part is very tricky. You may want to practice it a few times over the sink with a jar of plain water. Pick up the blue jar and turn it straight upside-down. You don't need to put your hand on the card. The water will hold the card in place. (Just flip the jar over. Don't hesitate. If the jar is tilted but not turned over completely, the water will gush out and make a mess.)
Lay the square card carefully onto the top of the blue jar. Tap the card gently with your finger. (Don't poke it. You want the card to be flat and form a seal with the water and the jar.)
Put the upside-down blue jar right on top of the red jar.
Have someone hold onto both jars while you very slowly and carefully pull the card out.
What happens? What color is the water in the top jar? What color is the water in the bottom jar?
Empty both jars. Rinse them. Repeat steps 1 through 6--but put the jar with the blue-colored cold water in the baking pan and put the card on top of the jar with the red-colored hot water. Turn the red jar upside-down and put it on top of the blue jar.
Slowly pull out the index card. What happens? What color is the water in the top jar? What color is the water in the bottom jar?
