A compound is a substance that consists of 2 or more elements chemically combined in a fixed proportion.
Compounds can be broken down ijt0 simple substances by chemical means but, elements cannot.
<span>The half-life of 9 months is 0.75 years.
2.0 years is 2.0/0.75 = 2.67 half-lives.
Each half-life represents a reduction in the amount remaining by a factor of two, so:
A(t)/A(0) = 2^(-t/h)
where A(t) = amount at time t
h = half-life in some unit
t = elapsed time in the same unit
A(t)/A(0) = 2^(-2.67) = 0.157
15.7% of the original amount will remain after 2.0 years.
This is pretty easy one to solve. I was happy doing it.</span>
-Pure magnesium is commonly made by separating it from seawater. This process is known as electrolysis. The liquid magnesium formed is cooled into convenient blocks of metal known as ingots. The chlorine gas is recycled to form hydrochloric acid for the production of more magnesium chloride.
Answer:
Covalent
Explanation:
A molecule of C₂H₅OH has C-C, C-H, C-O, and O-H bonds.
A bond between A and B will be ionic if the difference between their electronegativities (ΔEN) is greater than 1.6.

No bond has a large enough ΔEN to be ionic.
C₂H₅OH is a covalent molecule.
Answer:
True
Explanation:
They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone, making them the simplest out there