题干

善于归纳知识,利于培养素质.下面是小青同学对初中所学部分化学知识的归纳,其中有错误的是(  )

A

安全常识

B

物质鉴别

①使用煤炉子取暖﹣注意室内通风,防止一氧化碳中毒

②浓硫酸沾到皮肤上﹣立即用水冲洗

①食盐与纯碱﹣加入食醋

②氧气与二氧化碳﹣用燃着的木条

C

实验误差分析

D

实验操作顺序

①实验室配制一定溶质质量分数溶液,量取水的体积时仰视读数,使实验结果偏大

②测定盐酸溶液pH值时先用水将pH试纸湿润后再滴入试液,所得pH值偏大

①先检验装置气密性,再加药品

②加热固体时先均匀加热,再固定加热

A:A

B:B

C:C

D:D

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答案(点此获取答案解析)

C

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    The day finally came,when I had to leave the warm home where I'd grown up.I ran to the back yard,as tears came up from my heart.Suddenly I1a hand rest on my shoulder.I looked up to2mygrandfather.“It isn't3,isit,Billy?”he said softly.

    Gently4myhand in his,we walked,hand in hand,tothe front yard,5a hugered rose­bush sat alone.

    “What do you see here,Billy?” he asked.I looked at the flowers,not knowing6to say,and then answered,“I see something soft and7,grandpa.”

    He pulled me8.“It isn't just the roses that are beautiful,Billy.It's that special place in your heart that makes them so.”“Billy,I9these roses when my first son was born.It was my10of saying 'thank you' to God.I11to watch him pick roses for his mother. Then, as a young man of only 20,a terrible war robbed him of his life.” Grandpa slowly stood up.“Never say good­bye,Billy. Never12to the sadness and the loneliness.Instead,I want you to remember the joy and the13when you first said hello to a friend.”

    A year later,my grandpa became very14.Then all members of the family were15back,and I returned to the old house. When it came to my16,I took his hand as17as  he had once taken mine.

    “Hello,grandpa,”I18.His eyes slowly opened and said,“Hello,my friend.” With a brief19he died. Suddenly,and truly.I knew what he had20about never saying good­bye—about refusing to give in to sadness.