Are magic potions real?

Maria learned in school that she can make a dull penny shiny again with vinegar and salt. Maria thought this was fun, and it gave her an idea for a new experiment.
Maria is from Spain, and she has a coin from there called a 1 Euro cent. Maria’s 1 Euro cent looks a lot like the dull, brown pennies from her class. She was curious if she could do some new things with her Euro cent.

Before she did any experiments on her dull, brown 1 Euro cent, she asked her teacher for a scale. She put the coin on the scale.

Looking at the graph, how much does the coin weigh?

Tags

NGSS.MS-PS3-1

Now that Maria knew how much the coin weighed, it was time to experiment. She took a small piece of sandpaper and scratched it all over the coin. Dull, brown bits of stuff fell off wherever she scratched the coin. After a few minutes of scratching, the coin became shiny, and there was a small pile of dull, brown bits. She put the coin back on the scale now that it was shiny. Then she put the pile of dull, brown bits on the scale.  Look at each bar graph with her measurements.

How much does the shiny coin weigh now?

Tags

NGSS.MS-PS1-2

How much does the pile of dull, brown bits weigh?

When the sandpaper scratched the coin, it added new, shiny stuff onto the coin. The shiny stuff made the coin heavier.

• True

• False

The little brown bits were probably scratched off of the coin. That’s why the weight of the coin went down.

• True
• False

The sandpaper made the coin shiny, but nothing was added to it or scratched off of it. The dull, brown bits probably came from the sandpaper instead.

• True
• False

Maria wanted to know what would happen if she put the pile of dull, brown bits into a bag with vinegar and salt. She got a little tub with vinegar and salt in it, and she set it onto a scale to see how much it weighed. Then she dumped the little pile of bits into the tub, and watched what happened. The image shows what she saw.

True or False: After 1 minute, the dull, brown bits are no longer visible. They aren’t in the tub at all any more. They’re totally gone! That’s why the total weight went down, and that’s why Maria couldn’t see them anymore.

• True
• False

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

True or False: After 1 minute, the dull, brown bits broke down into tinier and tinier pieces. Those tiny pieces were too small to see, but they were still in the tub. The weight went up because there were so many teeny tiny pieces.

• True
• False

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

True or False: After 1 minute, the dull, brown bits broke down into even smaller little bits. Those little bits were too small to see, but they were still in the tub. Those little bits all add up to the same amount of stuff as it was to start with, though. That’s why the total weight stayed the same.

• True
• False

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5