The poly atomic ion formula for ammonium would be NH4+
B) oxygen, because oxygen is the only element that is in both chemical formulas.
The answer is A cause the water breaks down the rocks into small pieces which are called sediments. These things later on turn into rocks with pressure and heat
The features that are shared by the rocks include the melting and cooling of rocks.
<h3>What is a rock? </h3>
It should be noted that a rock simply means a relatively hard naturally occurring mineral material.
Crystals most often form in igneous and metamorphic rocks. The processes that these rocks share that likely promote the formation of crystals is the melting and cooling of rocks.
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The error caused will lower the number of moles when he did not do the second heating.This question is related to the empirical formula.
<h3>What is Empirical formula ?</h3>
A formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.
The empirical formula is the simplest ratio of atoms in a given compound.
we know that heating is used to eliminate most of the water molecules which are attached to the compound in the question, it's given that the second heating was not performed by the students.
This means that there are still some water molecules attached to the compound. This will imply that higher mass will be calculated for the compound because the water molecules are also considered.
So now, if we look at the calculation for the number of moles of water in this, we can say that this will be lower than the actual amount.
This is because there are some unaccounted moles of water which are still attached to the compound and these will be accounted in the compound mass rather than the waters. Therefore, the number of moles will be lower.
Hence, The error caused will lower the number of moles when he did not do the second heating.
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