题干

玻璃棒是中学化学实验中常用的仪器.下列实验过程中,一般不需要用玻璃棒的是  ____ (填写编号)

①粗盐提纯

②配制一定物质的量浓度的氯化钠溶液

③将适量氯化铁饱和溶液滴入沸水中制备氢氧化铁胶体

④探究Ba(OH)2•8H2O晶体和NH4Cl晶体反应过程中的能量变化

⑤实验室用新制的FeSO4溶液和预处理过的NaOH溶液制备Fe(OH)2白色沉淀.

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③⑤

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A Meaningful Gift

    Emily was an eight grader. To pass her Civics course(公民课程),she had to do some volunteer service in a nursing home for a week.

    One Monday, Emily went to the nursing home after school. When she arrived, she was told she would1an hour every weekday with an elderly lady, Mrs. Blair. She was then led into a room, where an old lady in a flowery dress was sitting on a sofa.

    Emily2awkwardly(别扭地) in front of the lady. She cleared her throat and said,“Good afternoon. I'm Emily.”

    “Good afternoon, Emily. Take a seat,please,”Mrs. Blair replied.

    Then,3filled the space between them. Emily wondered what to say.

    “Tell me about yourself,Emily,”Mrs. Blair said suddenly.

    “Well,” Emily started, “I don't have any grandparents, so I can't relate to elderly people much. I love the performing arts. I'm here mainly because I have to 4here to get a good grade for my Civics class.”Mrs. Blair didn't seem to5.Many people, especially teens, don't seem to care about old people like me. Now you're here, and I'm going to change that about you. Ask me anything.”

    Emily thought for a moment, and finally decided, “What was your job?”

    “I was a Broadway star in the 1950s,”Mrs. Blair answered.

    “Cool! Can you tell me about it?” Emily asked, amazed.

    Mrs. Blair smiled. “Back then, only the lead actress had the honor to wear a 6bracelet. I was the lead in almost all of the plays, so I always wore the bracelet. Till this day, I still have it.”

    Emily smiled along with Mrs. Blair and listened to the other stories, attentively. She had become so interested in Mrs. Blair's7that she decided to come earlier the next day.

    Tuesday, Wednesday, and Thursday passed by quickly. Then came Friday. As she was leaving, Emily was really8to say goodbye.

    “Don't be sad. You can still visit me,” Mrs. Blair comforted her. She then handed a small box to Emily, “It's my gift to you.”

    Emily9opened the box and was surprised to see what was inside. “It's the bracelet that you wore. Thank you!” Emily said, with tears in her eyes. “I'm sure to visit you whenever I'm free.”

    On her way home, Emily thought of her own love for the performing arts. She touched the bracelet and made a10that she would keep her word to Mrs. Blair.