题型:问答题 简答题 I can play ______ basketball but I can't play ______ piano. [ ]A. the; / B. /; the C. /; / D. the; the 查看答案
题型:问答题 简答题 25℃时,a mol•L-1一元酸HA与b mol•L-1NaOH等体积混合后,pH为7,则下列关系一定正确的是( )A.a=bB.a>bC.c (A-)=c(Na+)D.c (A-)<c(Na+) 查看答案