The chemical equation below shows the reaction between tin (sn) and hydrogen fluoride (hf). sn + 2hf mc017-1.jpg snf2 + h2 the molar mass of hf is 20.01 g/mol. how many moles of sn are required to react with 40 g of hf?

Tin and Hydrofluoric Acid reacts as shown,

                              Sn  +  2 HF    →    SnF₂  +  H₂

According to Equation,

40.02 g (2 Moles) HF Required  =  1 Mole of Sn for complete Reaction

So,
              40 g of HF will require  =  X Moles of Sn

Solving for X,
                                       X  =  (40 g × 1 Mole) ÷ 40.02 g

                                       X  =  0.999 Moles  ≈  1 Mole
Result:
            40 g of HF requires 1 Mole of Tin (Sn) for complete Reaction to produce SnF₂ and H₂.