1) deep trenches
2) active volcanoes
3) arcs of islands along the tectonic boundaries
4) in some cases, mountain ranges
The maximum negative displacement of a wave is the same as its amplitude.
As a wave travels through space, its particles are sometimes above the
<em>x</em>-axis (+) and sometimes below it (-).
The maximum displacement from the axis is the <em>amplitude</em> of the wave.
The amplitude of the wave is the <em>same in both the positive and negative directions</em>.
Answer:
B. Ca(NO2)2
Explanation:
Ions (charged atoms) combine with one another to form stable ionic compounds. In this case, calicium ion (Ca2+) is said to react with NO2, which has a charge of -1 i.e. +1-1(2) = 1-2 = -1.
This means that calcium has a charge of +2 while nitrite ion has charge of -1, hence, when they combine, they exchange their charges, which become their subscript as follows:
Ca2+ + NO2- → Ca(NO2)2
Ca(NO2)2 is a stable ionic compound called calcium nitrite. Notice that it takes two atoms of NO2- to react with one atom of Ca2+.
