2)As figuras a seguir constituem os sistemas fechados nós quais as bolinhas representam átomos. Classifique os sistemas I II III IV em substância composta ou mistura . I: II: III: IV: me ajuda prf​

Achemistry student weighs out 0.306 g of citric acid (h3c6h5o7), a triprotic acid, into a 250 ml volumetric flask and dilutes to the mark with distilled water. he plans to titrate the acid with 0.1000 m naoh solution. calculate the volume of naoh solution the student will need to add to reach the final equivalence point. be sure your answer has the correct number of significant digits.

Which of the following are correct values for the ideal gas laws constant r

What prefix multiplier is appropriate for reporting a measurement of 5.57 ×10−5 m?