# 單操輸送題目

Concentration of NaCl Solution.

An aquesous solution of NaCl has a concentration of 24.0wt% NaCl with a density of 1.178g/cm3 at 25度c. calculate the following.

(a)Mole fraction of NaCl and water.

(b)Concentration of NaCl as g mol / liter，1b m / ft3 ，1b m /gas，and kg/m3

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• 9 年前
最佳解答

Concentration of NaCl Solution.

An aquesous solution of NaCl has a concentration of 24.0wt% NaCl with a density of 1.178g/cm3 at 25度c. calculate the following.

(a)Mole fraction of NaCl and water.

(b)Concentration of NaCl as g mol / liter，1b m / ft3 ，1b m /gas，and kg/m3Sol: 為了方便計算, 以1000 ml (1 liter)來計算1000 ml NaCl 溶液重 = 1000*1.178=1178 gNaCl重 = 1178*24.0%=282.72 gH2O重 = 1178-282.72=895.28 gNaCl 分子量=23+35.5=58.5 (Na:23, Cl:35.5)282.72 g NaCl 之莫耳數 = 282.72/58.5=4.83 moleH2O分子量 = 1*2+16=18895.28 g H2O之莫耳數 =895.28/18=49.74 mole(a) molar fraction of NaCl = 4.83/(4.83+49.74)=0.0885 molar fraction of H2O = 49.74/(4.83+49.74)=0.9115(b) Concentration of NaCl as g mol / liter = 4.83/1 = 4.83 g mol / liter單位換算: 請參考http://www.measuring.org.tw/convert_30.htm1lbm/ft^... kg/m^3＝0.016018 g/cm^3 (也可以用 1lbm=0.454kg，1ft=0.348 m 自行計算出來)所以 1.178g/cm^3 = 1.178/0.016018 lbm/ft^3 =73.54 1lbm/ft^3 1.178g/cm^3 = (1.178/1000 kg)/(0.01 m)^3=1178 kg/m^3 1b m /gas??? 是什麼單位啊!

參考資料： 電腦週邊急救團