Well it's definitely not visible or thermal, so it's <u>electromagnetic waves</u><u>.</u>
<span>Pitch is sometimes defined as the fundamental frequency of a sound wave (i.e. generally, the lowest frequency in a given sound wave). For most practical purposes, this is fine, and pitch and frequency can be thought of as equivalent. On the other hand, for most practical purposes, amplitude can be thought of as volume.However, technically, pitch (and volume) are human perceptions. Thus, our perception of pitch and volume are not solely based on frequency and amplitude respectively, but are based on a combination of both (and even other factors). Frequency overwhelming dictates perceived pitch, but amplitude also does have some small, small effect on our pitch perception, especially when it is very large. For example, a very loud sound can have a different <span>perceived </span>pitch than you would predict from its frequency alone.That all being said, usually these effects are negligible, and pitch can be thought of as equivalent to fundamental frequency.
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Explanation:
(a) potassium oxide with water

According to reaction,1 mole of potassium oxide reacts with 1 mole of water to give 1 mole of potassium hydroxide.
(b) diphosphorus trioxide with water

According to reaction,1 mole of diphosphorus trioxide reacts with 2 moles of water to give 2 moles of phosphorus acid.
(c) chromium(III) oxide with dilute hydrochloric acid,

According to reaction,1 mole of chromium(III) oxide reacts with 6 moles of hydrochloric acid to give 2 moles of chromium(III) chloride and 3 moles of water.
(d) selenium dioxide with aqueous potassium hydroxide

According to reaction,1 mole of selenium dioxide reacts with 2 moles of potassium hydroxide to give 1 mole of potassium selenite and 1 mole of water.
From the calculation, the moles of water produced is 18 moles of water.
<h3>What is a decomposition reaction?</h3>
A decomposition reaction is one in which a substance is split up into smaller parts.
We have the reaction; 2 Cr(OH)3(aq) ------------> Cr2O3(s) + 3H2O(l)
From this reaction;
2 moles of Cr(OH)3 produced 3 moles of water
12 moles of Cr(OH)3 will produce;
12 moles * 3 moles / 2moles
= 18 moles of water
Hence, 12 moles of chromium (III) hydroxide produces 18 moles of water.
Learn more about decomposition reaction:brainly.com/question/8009068?
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