Nuclear fusion in the sun involves hydrogen (H) atoms
combining to form helium (He). A student claims that since the atmosphere
contains hydrogen, any fusion reaction on Earth would result in an uncontrolled
chain reaction. What is wrong in the student’s reasoning is that the uncontrolled
chain reactions can only happen during nuclear fission.
Answer: Molecules only speed up when given energy, such as heating. When you heat water enough, it will boil and turn into water vapor. So, therefore, if water's molecules speed up, it will go into the gas phase
Explanation: As that liquid water is further heated, it evaporates and becomes a gas—water vapor. These changes between states (melting, freezing, and evaporating) happen because as the temperature either increases or decreases, the molecules in a substance begin to speed up or slow down.
Hope this helps! ^w^
Answer: The periodic table
Explanation: Demetri Mendeleyev is famous for developing the periodic table. He introduced it in 1869.
1. Elements are composed of atoms that are indestructible
2. All atoms of a given element are identical; same size/mass/chemical properties
3. Atoms of 1 element are different from the atoms of other elements
4. Compounds are composed of atoms with more than 1 element. The relative number of atoms for each element are of a given compound are always going to be the same.
(Extra one) 5. Chemical reactions are only ever going involve the rearrangement of the atoms. Atoms are not created/destroyed during the chemical reactions. (Law of Conservation of Mass: nothing can ever be created or destroyed.)
