(Moles, particles, atoms)
Ex: How many grams of Ca are produced if there are 4.24 moles of HBr?
1). Balance the eq'n: 2Ca+2HBr--->2CaBr+1H2
2). Next make a road map: 4.24 mol HBr---> ?grams Ca
3). Now do the calculation: 4.24 mol HBr x 1 mol Ca x 80.2g Ca = 85g Ca.
2 mol HBr 2 mol Ca
Try some practice problems:
1) How many moles of HCl are needed to produce .76 g of CaCl?
2) How many grams of Ca are needed to produce 1 molecule of H?
3) How many atoms of H will be formed when 3.42 moles of Cl are formed?
4) How many grams of CaCl are needed to form 8.19 moles of HCl?
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