题干

下列叙述中不正确的是(   )

A:一定浓度的醋酸钠溶液可使酚酞溶液变红,其原因是发生了如下反应:CH3COO+H2O⇌CH3COOH+OH,使得溶液中的c(OH)>c(H+

B:在常温下,10 mL 0.2 mol•L1盐酸与10 mL 0.2 mol•L1 Ba(OH)2溶液充分混合,若混合后溶液的体积为20 mL,则溶液的pH=13

C:在0.1 mol•L1 NH4Cl溶液中:c(H+)+c(NH4+=c(Cl

D:5 mL 1 mol•L1 CH3COONa溶液与5 mL 1 mol•L1盐酸混合液中c(Cl)=c(Na+)>c(H+)>c(OH

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C

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    As a child, I started learning to play the piano, my favorite musical 1 but I was forced to give up when I started my middle school2 I could concentrate more on my studies.

    It's one of my biggest3 to stop practicing the piano when I recall sadly today. During the following years, I kept telling my piano teacher that I would4However, I didn't keep my promise because I was 5 with my study6 I lost touch with my teacher. Some years later, my teacher died. I was very sad because I lost such a good teacher. She was a very warm and gentle person. It hurts me to think she may have been 7 that I never returned. I haven't taken lessons since then but to be honest, I 8 to. Sitting at the piano, I couldn't help recalling many 9 ---times of my practising at home and playing before my teacher and one time my teacher 10 me after I played entire pieces of music wrong in front of her colleagues. I was so 11 that I could hardly say anything. But her 12helped ease my shame. These memories13good or bad, never caused my14 for playing the piano again.

    This thought then led me to think that 15 is like music, and that we all try to play different 16 in the instrument of our life. Sometimes the pitch (音高) is17when we play it well, but sometimes we are out of tone. However, we all continue to create our own 18style of music. No matter what style our music is, it is 19 that we sing the songs of joy, quietness and love. Though I may never make it back to piano lessons, it doesn't 20 that I've stopped making music.