Chromium is in Group 6, so elemental chromium has 6 valence electrons. Therefore, chromium 3+ has three 3d-
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Eggshells are made primarily of calcium carbonate. The acid in vinegar softens the calcium of the eggshell. Adding a little vinegar to the water when boiling eggs is an old cook’s trick that makes them easier to peel.
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Answer:
About 5 times faster.
Explanation:
Hello,
In this case, since the Arrhenius equation is considered for both the catalyzed reaction (1) and the uncatalized reaction (2), one determines the relationship between them as follows:

By replacing the corresponding values we obtain:

Such result means that the catalyzed reaction is about five times faster than the uncatalyzed reaction.
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A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in another