Según el estudio de la materia, es todo lo que se puede representar con un símbolo o con una formula química. A) El peso.

B) Las mezclas.

C) Las sustancias puras.

D) Los pesos específicos.

brain development. a child's brain undergoes an amazing period of development from birth to three—producing more than a million neural connections each second. the development of the brain is influenced by many factors, including a child's relationships, experiences and environment.

explanation:

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds

light dependent reactions:

light independent reactions:

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