meaning:An acid is a chemical substance, usually a liquid, which contains hydrogen and can react with other substances to form salts. Some acids burn or dissolve other substances that they come into contact with.
Answer:
B. Electrons are gained, so the oxidation number decreases.
Explanation:
Reduction is the <em>gain of electrons</em>.
Oxidation number is the charge that an atom <em>appears</em> to have when we count its electrons in a specific way.
Electrons have a negative charge so, if an atom gains electrons, its charge (oxidation number) becomes more negative. The oxidation number decreases.
If electrons are given off, the atom is being oxidized. Loss of electrons is <em>oxidation</em>.
An Endothermic change is a process in which there is absorption of energy.
-Condensation is the transformation from a gas to a liquid. So the water molecules releases energy while condensing, so condensation is exothermic (opposite of endothermic, it's the release of energy)
-Vaporization is the transformation from a liquid to a gas. When you heat water to evaporate it, you're giving energy to the water molecules. And when they absorb this energy, they transform to a gas. Which means that Vaporization is endothermic.
-Deposition is the transformation from gas directly to solid without passing by the liquid phase. Same as the condensation, but the water molecules release even more energy to directly become Solid. So deposition is exothermic.
-Freezing is the transformation from a liquid to a solid. During this phase, water molecules releases energy to its surrounding. So freezing is exothermic.
We can conclude that Vaporization is endothermic, because it's absorbing energy to transform from liquid to gas, while condensation, deposition and freezing are exothermic because they release energy to transform.
Hope this Helps! :)
Answer:
One.
Explanation:
Hello,
In this case, the equilibrium condition is characterized by the equality of the rates at which a process happen and the contrary process happen, so its ratio is 1. For instance, a chemical reaction at equilibrium will have a contant ratio of the velocity at which the products are formed and the reactants consumed
However, for the described insoluble solid that is allowed the reach equilibrium, the ratio of the rate at which ions join the solution and the rate at which ions join the lattice will be one since it reaches an equilibrium state.
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