The symbol Ca-40 denotes that

A. a calcium atom contains 40 protons

B. a calcium atom contains 40 electrons

C. a calcium atom contains 40 neutrons

D. a calcium atom has a mass number of 40

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How to write a word equation for CaCl2

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How do u find which is physical or chemical changes

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Which of the following is a chemical property? A.) Ability to burn B.) Mass C.) Density D.) All of the above

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In a popular classroom demonstration, solid sodium is added to liquid water and reacts to produce hydrogen gas and aqueous sodium hydroxide. part a write a balanced chemical equation for this reaction.

Calculate the vapor pressure lowering on an aqueous solution of glycerin that contains 180g of glycerin and 1000g of water at 25c. The vapor pressure of water at this temperature is 23.8torr.

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