Answer: 2. cannot be an element.
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Copper 
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: methane 
Thus as it can be decomposed into its constituent elements, it is a compound.
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present.
Thus methane cannot be an element.
this is the answer of your question .
<em>Hope</em><em> </em><em>it</em><em> </em><em>helped </em><em>you</em>
MgqI% = the formula and mass for H20 and that should be your answer for water
It doesn't because pepper does not dissolve
<span>
Low pH means the solution is acidic; if the solution is acidic, that
means that there are hydronium ions in solution (H3O+). For example,
hydrochloric acid dissolves into H+ ions and Cl- ions, and the H+ ions
rreact with water like this:
H+ + H2O --> H3O+
If you want to get mathematical, pH is defined as the negative log of the concentration of hydronium ions.
Thus, if there are a lot of hydronium ions, the solution will have a low, or acidic, pH. Hope this helps^-^</span>
