Answer is: <span>The general rule of thumb is that the smaller a substance's atoms and the stronger the bonds, the harder the substance will be.
If the distance between atoms is higher, lesser will be attraction between electrons and protons of atoms, smaller distance means stronger atoms attraction.
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A. It absorbs energy.
reactants are located on the left side of the equation, meaning energy among with other reactants were needed to get the reaction going, so it absorbed energy, which is also the endothermic process. The opposite of that would be having energy on the right side with the products which means that the reaction would've released energy which is the exothermic process. Hope this helps!
, we need to supply it
to make it
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