ATAR Notes: Forum
VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: nerdmmb on March 09, 2014, 11:03:58 pm
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I understand what n represents but I'm really confused about m and M.
My textbook notes that m represents the given mass of a substance and M is its molar mass...
and then it indicates that molar mass is the expression of the relative formula/molecular mass in grams..
I would really appreciate it if someone can please explain it to me and also provide an example :)
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I understand what n represents but I'm really confused about m and M.
My textbook notes that m represents the given mass of a substance and M is its molar mass...
and then it indicates that molar mass is the expression of the relative formula/molecular mass in grams..
I would really appreciate it if someone can please explain it to me and also provide an example :)
Molar mass (M) of any element is always constant and you can always refer to it by the periodic table (or try to remember some common one when you get used to them) whilst mass of a substance (m) is the amount of the compound that is given by the question.
For example, I have 5g of NaCl. Here, m = 5g and M = 58.5g/mol.
Hope this helps!
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Molar mass (M) of any element is always constant and you can always refer to it by the periodic table (or try to remember some common one when you get used to them) whilst mass of a substance (m) is the amount of the compound that is given by the question.
For example, I have 5g of NaCl. Here, m = 5g and M = 58.5g/mol.
Hope this helps!
You explain soooo much better than the book! Thank-you heaps!! :)
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molar mass (M) basically is all the added RAM of the elements in the compound. Mass is the gram value (g) of how much of that substance you have. Expanding on the NaCl question, if you have 5g its m=5g. The molar mass is M = Ar(Na) + Ar(Cl) - which by the looks of it is 58g/mol (58g mol-1)