Why does a penny turn green?

Why does a penny turn green?

When copper turns green-blue, that means the copper was oxidized by oxygen and chlorine (often found in salt). This oxidation reaction creates a different compound called malachite, which is green-blue in color. Keep the acid solutions that the pennies were soaking in to create copper coated nails.

How many drops of water did fit on the head of a penny?

The results indicate that when you drop water on a penny that the heads side of the penny will hold more drops (heads 23 drops, tails 18 drops).

How many drops of water are in the ocean?

There is an estimated 1.332 billion cubic kilometers of sea on Earth and 0.05 ml of water in a drop, so the ocean is equivalent to 2.664 × 10^25 drops or 26,640,000,000,000,000,000,000,000.

Why the coin appears raised in water?

This is because of refraction of light. As light passes from water to air, it bends away from the normal. The refracted rays appear to come from a point above the actual position of the coin, hence the coin appears raised.

What did you observe when you dropped water onto the coin?

Water’s cohesion and surface tension are special because of hydrogen bonds. The cohesion and surface tension of water becomes apparent when the drops of water you add to the penny reach the penny’s edge. Once the water has reached the edge, you begin to see a bubble or dome of water forming on top of the penny.

What happens to a penny when you put it in vinegar?

When you put your dirty pennies in the vinegar and salt, the copper oxide and some of the copper dissolve in the water. That means some copper atoms leave the penny and start floating around in the liquid.

Why didn’t the penny got stuck in the card as you performed the activity?

The coin has inertia, meaning it really wants to stay in one place. If you move the card slowly, it isn’t fast enough to overcome that force. If you flick it quickly, the coin stays in one place and then drops into the cup. An object at rest will remain at rest.