It is a physical change, because it does not change in substance. A penny, whether in its normal state or flattened, is still a penny. Similarly, if you drop a watermelon and it breaks apart, that is also considered to be a physical change because it is still a watermelon.
Things are considered to be chemical changes when the substance changes into something new, and is commonly classified as irreversible. When an object rusts, it is considered to be a chemical change. Chemical changes are associated with a temperature change, or a color change or bubbling or something of the sort. Physical changes deal with physical changes in state, for example, ice melting, or in the example you provided, a penny being flattened.
cause the value of the penny was more then wat it was worth
A good title for a penny experiment could be "Penny Power: Exploring the Science of Surface Tension." This title highlights the focus on the physical properties of pennies while hinting at an engaging scientific investigation. It invites curiosity and suggests a hands-on exploration of the principles at play.
100 penny makes a dollar. Every penny counts, my friend!
In this experiment, the control group would be the penny! The independent variable is the substance/water on the penny, and the dependent is how many drops the penny takes.
You pass a penny.You pass a penny.
Physical change
Chemical
Putting a penny in lemon juice would cause a chemical change because the lemon juice reacts with the copper in the penny to create copper oxide, which changes the chemical composition of the penny.
this is my homework just give the answer already!
Yes
Sugar reaches the copper and they form a physical change
Removing tarnish from a penny with salt and vinegar is a chemical change. The reaction between the salt, vinegar, and tarnish on the penny results in the formation of new substances that remove the tarnish.
Chemical.
It would depend on how enthusiastically you flattened it. Like a jeweller hammering out gold leaf, you could probably make it about a quarter the size of a tennis court if you had sufficient patience and skill.
Cleaning a penny with vinegar and salt is a chemical change. The vinegar (acetic acid) reacts with the salt (sodium chloride) to form a chemical compound that removes the tarnish on the copper surface of the penny. This reaction changes the composition of the penny's surface, making it appear shiny and clean.
Mike Hammer Private Eye - 1997 A Penny Saved 1-9 was released on: USA: 23 November 1997
It depends how you mean dull. Dull by wear or dull by oxidation? If it just becomes dull without being touched, then it is a chemical change. Metals readily react with non metals ie Oxygen. This will form a metal oxide layer on the exposed regions. This is why you need to sandpaper down some of the more reactive metals, when using them for conductivity experiments in school, as the oxide reduces conductivity.