What is the correct answer
Favorites|Homepage
Subscriptions | sitemap
HOME > Chemistry > What is the correct answer

What is the correct answer

[From: ] [author: ] [Date: 11-07-08] [Hit: ]
63kJ/mol) (180 g / 23 g/mol) = 20.Three sig figs is reasonable: 20.......
Given that the molar heat of fusion of sodium (Na <--solid) is +2.63KJ/mol, how much potential energy is needed to completely melt 180g of solid sodium at its melting point?

a) 2.63KJ
b) 2.98KJ
c) 20.6KJ
d) 473KJ

-
First you need to know how many moles of sodium you have. The atomic weight (molar mass) of sodium is 23 (rounding a little bit). So 180 grams / 23 grams per mole = 7.83 moles. The heat of fusion is 2.63 KJ/mol, so 7.83 multiplied by 2.63 = 20.58 which rounds to 20.6 which is "c"

-
(2.63kJ/mol) (180 g / 23 g/mol) = 20.5826 kJ

Three sig figs is reasonable: 20.6 kJ
1
keywords: the,What,correct,is,answer,What is the correct answer
New
Hot
© 2008-2010 http://www.science-mathematics.com . Program by zplan cms. Theme by wukong .