A student is going to prepare a 250cm^3 solution of oxalic acid from its pure crystals ((COOH)2 ●2H2O).he weights out 1.8 g of oxalic acid crystals and dissolves them in 25 cm^3 of distilled water. Then the solution is diluted to 250cm^3
a) Calculate the no of moles of oxalic acid obtained from 1.8 g of its crystals.
b) Calculate the majority of the 25cm^3 solution of oxalic acid.
c) Calculate the majority of the solution of oxalic acid after it has been diluted to 250 cm^3.
Easy chemistry questions
2008-05-10 1:54 am
回答 (2)
2008-05-10 3:17 am
✔ 最佳答案
a) the molar mass of oxalic acid=126gtherefore the no. of mole=1.8/126=0.0143mole
b) the molarity of acid in 25cm3 solution=0.0143x1000/25
=0.57M
c) the molarity of diluted solution=0.57x1/10=0.057M
2008-05-12 1:09 am
a. molar mass of the crystal=(12+16*2+1)*2+2*(16+1*2)=126 g/mol
No. of mole of acid obtained= 1.8/126 =0.143mole
b. majority of the acid= 0.143/(25/1000) (majarity=mole/volume)
= 5.72M
c. let the majority of the dil. acid be m,
by v1*m1=v2*m2,
5.72*25/1000=m*250/1000
m=0.572M
No. of mole of acid obtained= 1.8/126 =0.143mole
b. majority of the acid= 0.143/(25/1000) (majarity=mole/volume)
= 5.72M
c. let the majority of the dil. acid be m,
by v1*m1=v2*m2,
5.72*25/1000=m*250/1000
m=0.572M
參考: 自己
收錄日期: 2021-04-18 15:51:41
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