Solución: El problema indica que se le están suministrando 700 calorías de calor, eso quiere decir que Delta Q será positivo, por otra parte nos dice que al sistema se le aplicará un trabajo de 900 Joules, aquí el signo de Delta W tendrá que ser negativo, puesto que se la están aplicando al sistema.
Sabiendo ese análisis podemos dar solución al problema de la siguiente forma:
Chloroplasts contain chlorophyll which is what makes plants green. Onions are not green because they do not contain chloroplasts. The reason they do not have chloroplasts is because in the chloroplast, photosynthesis takes place. A key player in the process of photosynthesis is the sun. The onion itself grows underground which means while they grow they do not come into contact with the sun so chloroplasts in an onion is pointless since they can’t undergo photosynthesis. Hope I helped!
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