It was first introduced in1885
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Answer:
In the first one in a it is red light in b it is radio waves in c it is infrared radiation and d is UV radiation
Explanation:
Answer:
- <em>The net charge of the ionic compound calcium fluoride is </em><u><em>zero (0).</em></u>
<em>Explanation:</em>
<em>Ionic compounds,</em> such as covalent ones, have zero net charge; this is, they are neutral.
Substances with net positive charge are cations and substances with net negative charge are anions.
The charges in the <em>ionic compound calcium flouride</em> are distributed in this way:
- Calcium charge: Ca²⁺: this is, each calcium ion has a 2 positive charge
- Fluoride charge: F⁻: each fluoride ion has a 1 negative charge.
- Then, the <em>net charge</em> is: 1 × (2+) + 2 × (1-) = +2 - 2 = 0.
So, a two positve charge, from one calcium ion, is equal to two negative charges, from two fluoride tions, yielding a <u>zero net charge</u>.
Answer:
the answer is 10
Explanation:
Al2 is 2 atoms by itself
(SiO3)2 is 8 because Si is a single atom and O3 is 3 oxygen atoms but because of the subscript outside of the parentheses it doubles and becomes 2 and 6 respectively
