Answer:
Noble Gases
Explanation:
The Noble Gases have a full valence shell of 8 electrons. They are stable in that sense.
Answer:
1-Pentene
Explanation:
If we look at all the options listed, we will notice that the rate of reaction of bromine with each one differs significantly.
For 1-pentene, addition of bromine across the double bond is a relatively fast process. It is usually used as a test for unsaturation. Bromine water is easily decolorized by alkenes.
Cyclohexane, heptane are alkanes. They can only react with chlorine in the presence of sunlight. This is a substitution reaction. It does not occur easily. A certain quantum of light is required for the reaction to occur.
For benzene, bromine can only react with it by electrophilic substitution in which the benzene ring is retained. A Lewis acid is often required for the reaction to occur and it doesn't occur easily.
Cells are too small to see with the naked eye.
It's pretty straight forward, use the cross-out method.
1) Microscopes MAGNIFY images, they don't color the cells. In fact, scientists have to use these chemicals to "stain" or color the cells to see them more easily through microscopes.
2) If the lenses of a microscope reduced the image of an organism to the size of a cell, you'd be seeing a very tiny human through your microscope, instead of actual cells.
3) Microscopes don't "trap" anything. In fact, scientists use plates or slides under microscopes to contain what they're studying.
Answer:
18,01528
Explanation:
Democritus *suggested* the existence of the atom, that everything was made up of tiny particles, but wasn't really able to get more specific than that. Dalton also theorized that everything was made up of indivisible particles, but went further basing his theory on actual scientific principles, such as the Law of Conservation of Mass and the Law of Constant Composition. He also said that atoms weren't created or destroyed in a chemical reaction, just rearranged. There's more to it than that, but basically, Dalton's theory was based more on science while Democritus' theory was too general to be useful in chemical situations.
