题干

配制200mL 0.100mol•L﹣1盐酸溶液时,下列实验操作使所配的溶液浓度偏大的是(   )

A:用量筒量取所需的浓盐酸时仰视读数

B:用量筒量取的浓盐酸时,量筒里有少许蒸馏水

C:定容时,仰视标线

D:定容后倒转容量瓶数次摇匀,发现液面最低点低于标线,再补加几滴蒸馏水至标线

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A

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    Growing up in Puerto Rico, our family was no different from so many others. My parents got married after my father came back when the war ended. Both of my parents were struggling with the hard economic realities of the time. But somehow, they found time to cherish those cultural values that shaped our everyday life.
    In our daily life, we celebrated together with our friends or family members every birthday, every graduation, and all holidays with music and dancing, and typical foods. When we visited our family in the countryside—a trip that took about two hours in a car, with five children fighting as to who would get a window or the front seat —we would break into song, and somehow the trip would turn into one full of happiness and fun. We would sing not only interesting children's songs but also beautiful love songs — songs about the love of our country though we didn't understand the meaning of the words many times.
    I came to Philadelphia for the first time in 1973 to do a residency(实习) in family medicine. I remember the many hours of work. I was facing issues of life and death and suffering the clearly social unfairness and issues of poverty and race. These were all worsened by my feeling of cultural differences.
    An important turning point in my life happened one Saturday night when I attended a concert of Puerto Rico singer and composer Antonio Caban Vale. The music showed my familiar rhythms, and the words spoke to my heart. I had found a space to express, celebrate, and share my culture in Philadelphia. Therefore, I believe diversity is seen as an advantage and not as a disadvantage. As a Puerto Rican, I am a mixture of races and I believe in my strength because of this.