Answer:
The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Aluminium, or 26.981538 grams.
Answer:- 
Explanations:- The first reaction is combustion reaction as the hydrocarbon is burned in presence of oxygen to give carbon dioxide and water.
Second reaction is the synthesis reaction as in general a synthesis reaction looks like:

Third reaction is the decomposition reaction as it looks opposite of synthesis reaction.

In general, a single displacement reaction looks like:

Fourth reaction is single replacement reaction as bromine is replaced by chlorine.
So, the correct choice is the last reaction,
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I believe the correct response would be A. The cumulative nature of science. How experimental evidence and ideas made by many scientists have accumulated and or built up to have a more understandable and or clear view of a particular scientific topic, and or principle.
Answer: C2H4 + 3O2 → 2CO2 + 2H2O
Explanation:
2Al + 2O2 → 2AlO + O2 Not Balanced Properly: 2Al + O2 = 2AlO
C2H4 + 3O2 → 2CO2 + 2H2O Looks Good
2CH4 + O2 → 2CO + 4H2 Not Correct: CO should be CO2
Ca + O2 → CaOH Not Balanced and No source for the H
Answer:You didn't provide examples
Explanation: Groundwater can cause erosion under the surface as it moves through the soil. During the movement an acid is formed which what causes erosion and deposition.
Hope that helps