能用H++OH-=H2O表示的化学方程式是（ ）
A．氢氧化钠溶液与醋酸反应
B．氢氧化铁与硫酸反应
C．氢氧化钡与硫酸反应
D．硫酸氢钠与氢氧化钠溶液反应
A．醋酸为弱电解质，应写成化学式，不能用H++OH-=H2O表示，故A错误；
B．氢氧化铁难溶于水，应写成化学式，不能用H++OH-=H2O表示，故B错误；
C．氢氧化钡与硫酸反应生成硫酸钡沉淀和水，不仅仅发生H++OH-=H2O，故C错误；
D．硫酸氢钠与氢氧化钠溶液反应的离子方程式为H++OH-=H2O，故D正确．
故选D．
Lilly was a French Canadian girl who grew up in the farming community.When she was 16，her father____her to drop out of school to contribute to the family income.With English as her second language and____education，the____didn’t look bright for Lilly. Lilly’s father was a stubborn man who___took “no” for an answer.He____Lilly to find a job.With small hope of gaining____，each day she would just ride to the city，walk____about and return home at dusk. On one of her____，Lilly saw a sign at a big company.___，she knocked on the very first door.In her____English，Lilly told the office manager she was interested in the secretarial position.The manager ____to give the girl a chance.He directed her to type a letter，and then____.Lilly looked at the clock and saw it was 11∶40 am.She thought everyone would be leaving for____at noon，when she could____away in the crowd.But she knew she should____the letter. On her first try，Lilly____one line of five words and made four mistakes.On her second attempt，she completed a full paragraph，but still made many mistakes.She looked at the clock：11∶55—five minutes to____.Just then the manager walked in.He came directly to Lilly，read the letter and said，“Lilly，you’re doing____work！” With those simple words of encouragement，her desire to escape disappeared and her____began to grow.Lilly thought，“Well，if he thinks it’s good，then it must be good.I think I’ll stay！” Lilly did stay—all because someone had given a____and uncertain girl the gift of selfconfidence when she knocked on the door.
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