Density<span> is </span>defined<span> as the ratio between mass and volume or mass per unit volume.
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The product that is dissolved in the solution would be the salt zinc chloride. It is a substance that is soluble in water so it should be dissolved in the solution. Also, from the reaction, the sign (aq) is written. It means that this substance is in aqueous solution.
Answer:
Nucleus, golgi apparatus, cell membrane