How many moles of sodium cyanide (nacn) would be needed to produce 4.2 moles of sodium sulfate (na2so4)? h2so4 + 2nacn → 2hcn + na2so4

The purpose of a chemical equation is to relate the amounts of reactants to the amounts of products based on the rate each is consumed. In this problem, one mole of sulfuric acid is consumed along with two moles of sodium cyanide to produce two moles of hydrocyanic acid and one mole of sodium sulfate. The relationship between sodium cyanide and sodium sulfate is 2:1, meaning that two moles of NaCN is required to produce one mole of sodium sulfate.

To produce 4.2 moles of sodium sulfate, two times this amount of NaCN is required. This means that you would need 8.4 moles of sodium cyanide.

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