7. A conclusion is an educated guess,
or, prediction, about what will happen after the experiment.
8. In observation we use all five senses to gather information.
9. In result we analyze and summarize and ask if the hypothesis was correct.
10. Something that changes or varies in an experiment is called variable.
Ans:
Conclusion
Observation
Results
Variable
ok im not full sure man but i would say multiple voltaic cells that have spontaneous half reactions
im sorry hope it helps
The correct answers are options C, that is, silver tarnishes and becomes black when exposed to oxygen, and option E, that is, diesel fuel burns when it is heated.
Chemical changes refer to the modifications in which the chemistry at molecular level is modified as the initial substance gets transformed into a new and different final substance. This change occurs with the dissociation of old bond and production of new bonds respectively.
Silver gets tarnished and becomes black when exposed to oxygen. This refers to a chemical change as silver a white and lustrous substance gets transformed into a tarnish black final substance. However, silver does not easily react with oxygen at usual circumstances. It easily reacts with sulfur comprising components in the air and generates black compound as Ag₂S.
Burning of diesel fuel when it is heated. Diesel refers to a mixture of hydrocarbons varying approximately from C₁₀H₂₀ to C₁₅H₂₈. When these hydrocarbons get burnt they generate novel substances, that is, carbon dioxide and water. Hence, it is also a chemical reaction.
Answer:
Option A and D are correct.
Unstable species react rapidly.
Stable species do not react rapidly.
Explanation:
The complete question is attached to this solution.
The more stable a reactant is, the less reactive it will be. A stable reactant has a very stable structure in which it will avoid any perturbations. And for a reaction to occur, the bonds in the reactant must break down to form the products. A stable reactant has very strong bonds that aren't easy to break down, hence, reactions involving very stable reactants do not proceed rapidly.
And the more unstable a reactant specie is, the more rapidly it reacts. This is why the reaction involving the less stable isotope of carbon; Carbon-14 is very rapid. It is the same reason as explained above that is responsible for this. The bond between unstable species are not strong and are easily breakable, thereby leading to a quick reaction.
Hope this Helps!!!
A dissolving liquid composed of polar molecules is a polar solvent.
The distinction of polar and non-polar liquids is important because the like dissolves like rule. This rule states that the solubility is greater when the polarity of the liquid is similar to the polarity of the solute.
So, to dissolve polar compounds (e.g. ionic compounds) you should use polar solvents (e.g. water).
Answer: polar solvent
