La historia de la quimica se inicia con el descubrimiento de

Chemical science arises in the seventeenth century from the studies of alchemy popular among many of the scientists of the time. The basic principles of chemistry are considered to be collected for the first time in the work of the British scientist Robert Boyle: The Skeptical Chemist (1661).

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

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