Plz help me with these following questions as well.I've been trying to get the right answers for so long but i can't find it.but I do have the answers of the questions.what i need is the steps.2.What is the mass of 2.3 moles of aluminium oxide?3.What is the molar mass of tetrachloromethane, CCl4?4.How many moles of aluminium ions are present in 17.12g of aluminium sulphate?5.What is the formula mass of iron(II)Sulphate-7-water, FeSO4 7H20?I really need help in these questions.Thx
The formula Al2O3 means that 1 mole of Al2O3 has 2 moles of Al ions and 3 moles of O ionsSo, any sample of Al2O3 will always have a 2 to 3 ratio of Al and OIn your 0.4 mol of Al2O3, there are 0.8 mol of Al ions and 0.12 mole of O ions since 0.8 to 0.12 is a 2 to 3 ratio 2.3 mol times 101.961 g/mol 234.5103 g rounded off to two sig figs, the answer is 230 g one C + 4 Cl 12 + (4) (35.5) 154 g/mol Using better numbers gives 153.823 g/mol Al2(SO4)3 convert 17.12 g to moles by dividing by the molar mass of Al2(SO4)3 multiply moles by 2 Get a periodic table to look up atomic weights FeSO4 7H20 one Fe one S four O 7 H2O (H2O 18.015, after awhile one gets that value memorized) Add them upThe dot between the FeSO4 and the 7H2O is not a multiplication dot.
