Moles and Chemical Formulae Finding the Simplest Formula

Finding the Simplest Formula Imagine you react 2.6512 g of Zn is reacted with excess Cl2(g) When the Zn and Cl2 have finished reacting a white powder is left and has a mass of 5.4512 g What is the formula for zinc chloride?

Finding the Simplest Formula The simplest formula is obtained by dividing the number of moles of the elements by the smaller number of moles Use whole numbers as subscripts to write the formula Zn1Cl2 or ZnCl2

Magnesium Oxide Weigh crucible and cover Mcrucible Weigh out 0.15-0.300 g of Mg ribbon MMg Tightly roll Mg and place in the crucible in the fume cupboard using the set-up on the right With the lid off heat the crucible when the Mg ignites use crucible tongs to place lid on top of crucible When there is no smoke, take off lid and heat for 5 more minutes Let the crucible cool and add 15-20 drops de-ionized water and heat gently to evaporate water, then heat strongly for another 4 mins Allow to cool and weigh crucible and lid Mfinal