I believe it is b. you only want to change one thing at a time so you know which one thing caused the effect
The reactions are in order which includes combustion reaction, Hydration reaction, oxidation reaction, and displacement reaction.
a) A combustion reaction is a chemical reaction between a fuel and an oxidant where heat is released. The combustion reaction example is given below. It is a balanced chemical reaction.
2C₃H₆(g) + 9O₂(g) --------> 6CO₂(g) + 6H₂O(g)
b. A hydration reaction is a chemical reaction in which a molecule of water is added to another molecule. Here Aluminum oxide is added to water to form aluminum hydroxide.
4Al₂O3(s) + 6H₂O(l)------> 2Al(OH)3(s)
c. When a metal reacts with oxygen, the metal forms an oxide. Oxide is a compound of metal and oxygen. Here lithium metal reacts with oxygen to form lithium oxide.
2Li(s) + O₂(g)-----> Li₂O(s)
d. A displacement reaction is one in which a more reactive element displaces a less reactive element from a compound. Here Zinc is more reactive than silver, so silver was displaced to form Zinc Nitrate.
Zn(s) + 2AgNO₃(aq) -----> 2Ag(s) + Zn(NO₃)₂(aq)
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For the first one the answer is B. and the second one is D.
Answer:
Green plants and trees use photosynthesis to make food from sunlight, carbon dioxide and water in the atmosphere: It is their primary source of energy. The importance of photosynthesis in our life is the oxygen it produces. Without photosynthesis there would be little to no oxygen on the planet.
According to the research, domain is the taxonomic classification level that is the largest or most broad.
<h3>What is domain?</h3>
It is the broadest taxonomic category in which known living things are classified.
In other words, it is the broadest category in which the different kingdoms of life can be organized, according to the classification models that are most widely accepted in the scientific community.
Therefore, we can conclude that according to the research, domain is the taxonomic classification level that is the largest or most broad.
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