{"content":{"sharePage":{"page":0,"digests":[{"id":"13049475","dateCreated":"1246421485","smartDate":"Jun 30, 2009","userCreated":{"username":"shuangxing_S419","url":"https:\/\/www.wikispaces.com\/user\/view\/shuangxing_S419","imageUrl":"https:\/\/ssl.wikicdn.com\/i\/user_none_lg.jpg"},"monitored":false,"locked":false,"links":{"self":"https:\/\/liewsg.wikispaces.com\/share\/view\/13049475"},"dateDigested":1532092319,"startDate":null,"sharedType":"discussion","title":"question","description":"I don't understand how to do questions like 4 and 5 in worksheet 6.2. How do you relate the formula of the product to the molar mass of the reactants? - Shuang Xing","replyPages":[{"page":0,"digests":[{"id":"13050095","body":"No of moles = mass (in grams) \/ molar mass<br \/>\n<br \/>\nMolar mass is equal to relative formula mass.<br \/>\n<br \/>\ni.e. molar of mass of hydrogen = relative atomic mass of hydrogen = 1","dateCreated":"1246425344","smartDate":"Jun 30, 2009","userCreated":{"username":"danny_s415","url":"https:\/\/www.wikispaces.com\/user\/view\/danny_s415","imageUrl":"https:\/\/ssl.wikicdn.com\/i\/user_none_lg.jpg"}},{"id":"13050577","body":"e.g.we know that &quot;one water molecule contains one oxygen atom &amp; 2 hydrogen atoms&quot;. <br \/>\nNow extend this further by using a huge no like &quot; one mole&quot;[remember this 1 mole is equivalent to 6.02x 10^23.].<br \/>\nWe can say that &quot; 1 mole of water molecules contains 1 mole of oxygen atoms and 2 moles of hydrogen atoms.&quot;<br \/>\nNow, for your question:<br \/>\nYOu want to find out the chemical formuloa of hydrated magnesium sulfate which will look something like this = []MgSO4 . []H2O. <br \/>\nYou need to find out what is [ ]? Alternatively, You need to fond out how many units of MgSO4 will combine with how many units of H2O to form hydrated MgSO4, to phrase it another way, you need to find out how many moles of MgSO4 will combine with how many moles of H2O. <br \/>\nThat is Your problem.....<br \/>\nSearching for data now..you were given 12g of MgSO4 without water of crystallisation. and 12.6 g of water molecule.<br \/>\nTo determine the no of moles. use equation[no of moles = mass\/molar mass]<br \/>\nIs this explanation helpful? Got it ? :-)","dateCreated":"1246429016","smartDate":"Jun 30, 2009","userCreated":{"username":"Liewtsg","url":"https:\/\/www.wikispaces.com\/user\/view\/Liewtsg","imageUrl":"https:\/\/www.wikispaces.com\/user\/pic\/1246002418\/Liewtsg-lg.jpg"}}],"more":0}]}],"more":false},"comments":[]},"http":{"code":200,"status":"OK"},"redirectUrl":null,"javascript":null,"notices":{"warning":[],"error":[],"info":[],"success":[]}}