21.0 g of pure silver have a volume of 2.00 cm3. What is the density of silver?

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?

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For the reaction shown, calculate how many moles of no2 form when each of the following completely reacts. 2n2o5(g)→4no2(g)+o2(g) part a 1.0 mol n2o5 express your answer using two significant figures. nothing mol m o l request answer part b 5.4 mol n2o5 express your answer using two significant figures.