How many grams of NO2 are needed to form 88.0 g of HNO3?

64.4g

Explanation:

The chemical reaction that will produce HNO₃ from NO₂ is given below:

        3NO₂  +  H₂O →  2HNO₃  + NO

Given;

Mass of HNO₃  = 88g

  Now;

To solve this problem, find the number of moles of HNO₃;

  Number of moles  =  

      Molar mass of HNO₃ = 1 + 14 + 3(16) = 63g/mol

 Number of moles  =   = 1.40mol

From the balanced reaction;

    2 mole of HNO₃ is produced from 3 mole of NO₂

   1.4 mole of HNO₃ will be produced from   = 2.1mole of NO₂  

Mass of NO₂ = number of moles x molar mass

  Molar mass of NO₂ = 14 + 2(16) = 46g/mol

  Mass of NO₂ = 1.4 x 46  = 64.4g

the answer for sodium is 0.186

the answer for rubidium is 0.251

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.