Some things that can indicate a chemical change are change of odor, change of color, change in temperature or energy, such as the production or loss of heat. An example could be the rusting of metal, there would be a color change of going from a shiny silver to a dirty, splotchy red color. Some things that indicate a physical change are change of appearance like change of shape, etc. It can also be like a change between a solid to liquid to gas. For example, the cutting of a piece of paper.
The first pesticides relied on natural chemicals, such as those taken from chrysanthemum flowers is true
Answer:
Water (H2O) is polar due to the bent shape of the molecule. The shape means most of the negative charge from the oxygen is one one side of the molecule and the positive charge of the hydrogen atoms is on the other side of the molecule. This is an example of polar covalent chemical bonding.
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