Answer:
Pure elements:
Hydrogen(H)
Nitrogen(N)
Magnesium (Mg)
Pure Compounds:
Oxygen gas(O2)
Water (H2O)
Ammonia (NH3)
Explanation:
Hope it helps.Please mark me brainliest.^-^
Answer:
Organic compounds
Explanation:
I just did this question and apparently it’s that. (:
Answer : Option 4) 
Explanation : is the only sample of matter which can be classified as a solution. As the solution can be defined as a liquid mixture which contains a minor component (the solute) that is uniformly distributed within the major component (the solvent).
In this case, the solute is 
which is dissolved in water which acts as an solvent. Also, it has a subscript which is aq. which means aqueous, is often given to the solution in which the solvent is water.
Therefore, is the correct answer.
Answer: You multiply and divide when rounding division significant figures
Explanation: Both multiplying and dividing significant figures have the same rule. That rule is, the FINAL ANSWER of a multiplication and division problem should be rounded to the number of significant figures that is the least amount of any figures used in the multiplication or division. Let us demonstrate below.
