O nióbio é um metal encontrado em jazidas naturais, principalmente na firma de óxidos. Em uma jazida que contenha nióbio com número de oxidação +5, a formula do óxido predominante desse metal corresponde a:

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?

Surface currents are caused by blank space . question 14 options: surface currents are caused by? differences in water temperature high salinity differences in density wind forces

Achemistry student needs to standardize a fresh solution of sodium hydroxide. he carefully weighs out of oxalic acid , a diprotic acid that can be purchased inexpensively in high purity, and dissolves it in of distilled water. the student then titrates the oxalic acid solution with his sodium hydroxide solution. when the titration reaches the equivalence point, the student finds he has used of sodium hydroxide solution.calculate the molarity of the student's sodium hydroxide solution. be sure your answer has the correct number of significant digits.