很多酸、碱、盐之间都可以发生反应，进行的反应都属于基本反应类型中的复分解反应．
（1）酸碱之间的反应又可以称为______反应．
（2）20g氢氧化钠溶液和19.6g 25%的稀硫酸恰好完全反应．
求：氢氧化钠溶液的质量百分比浓度是多少？
（1）酸碱之间的反应称为中和反应，所以本题答案为：中和；
（2）设氢氧化钠的质量分数为x
H2SO4 +2NaOH═Na2SO4 +2H2O
98 80
19.6g×25% 20g×x
=98 19.6g×25% 80 20g×x
x=4g
NaOH溶液的质量分数为：
× 100%=20%4g 20g
答：氢氧化钠溶液的质量分数为20%．
| While much of the United States of America put Prohibition to rest 73 years ago, large parts of the South have remained strictly off-limits to alcohol sales. But local and national business interests that stand to profit from the sale of alcohol, including real estate developers, grocery chains, restaurant groups and Wal-Mart, are combining their political and financial muscle to try to persuade hundreds of dry towns and counties to go wet. In the process, they are changing the face of the once staunchly prohibitionist Bible Belt. Attempts by Wal-Mart and others to allow alcohol sales in other places that remain dry—415 counties in the South and in Kansas still prohibit such sales—are meeting fierce resistance from some church groups and religious leaders. They argue that returning to the days when liquor flowed will mean more family violence, underage drinking, drunken driving and a general moral decay in the community. Wal-Mart, based in a dry county in Arkansas, forbids drinking at events held at corporate headquarters. But the giant retailer has made a push in the last year to sell more liquor, along with beer and wine, in its stores. |
According to the passage, Wal-Mart is a ______ .
A．restaurant group
B．business interest
C．real estate developer
D．grocery chains owner