Answer:
D. Solutions are formed when the water’s polar molecules separate the polar molecules of an ionic or molecular compound.
Explanation:
Solutions are homogeneous mixtures formed by interaction between solutes and solvents.
Water based solutions have water as the solvents and mostly ionic and molecular compounds as their solutes.
Water is a polar solvent that is capable of dissolving many compounds by hydrating them. The molecules of water surrounds the solute and forces them to separate.
Answer:
Bubbling/Foaming
Heat is produced
Explanation:
A chemical reaction has occurred if
1. There is a change in colour
2. Formation of a precipitate
3. Formation of a gas
4. Change in temperature
5. Change of smell
In the reaction of hydrogen peroxide and potassium iodide, the solution quickly rises which shows the formation of gas. This means it is a chemical reaction.
The beaker/test tube/whatever you used should also become warm because it is an exothermic reaction. This means its a chemical reaction
he is a good scientist because he postulated that chemical reactions resulted in the rearrangement of the reacting atoms
Answer:
c. Only certain energies are allowed for the electron in a hydrogen atom
Explanation:
Emission spectrum are produced when the excited electron in a atom release the energy in the form of photons to come to ground state. These photons are of different wavelengths depending on the excitation state of emitting electron or transition of electron. These electromagnetic radiation are observed through prism to produce the spectrum.
As the name indicates this spectrum is produced by emission of energy. Although the electron can be excited by different methods such as by heating but the key point is that electrons in hydrogen atom will emit the photons of same energy which they absorb and each electron can absorb only certain type of energy. So four lines were observed in the visible spectrum of hydrogen because only certain energies are observed for hydrogen atom.
