It just is because science is science and it's supposed to make sense
First, it combines with carbon dioxide in the soil to form a weak acid called carbonic acid. ... Carbonic acid slowly dissolves away minerals in rock, especially the carbonate minerals that make up limestone and marble. The weak acid decomposes the insoluble rock into watersoluble products that move into the groundwater.
Answer:

Explanation:
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In this case, for such formation of sulfur hexafluoride, the standard enthalpy of formation is -1220.47 kJ/mol (data extracted from NIST database). Next, we compute the moles in 10.0 grams of sulfur hexafluoride as shown below:

Next, for the given energy, we compute the total heat that is liberated:

Finally, we conclude such symbol has sense since negative heat is related with liberated heat.
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Two types of chemical bonds common in compounds are covalent bonds and ionic bonds. The elements in any compound are always present in fixed ratios. Example 1: Pure water is a compound made from two elements - hydrogen<span> and </span>oxygen<span>.</span>
Answer:<em> A transfer of electrons occurs when fluorine and calcium react to form an ionic compound. This is because calcium is in group two and so forms ions with a two positive charge. ... A pairs of shared electrons makes one covalent bond. The compound formed is known as a molecule***</em>