已知某温度下，四种一元弱酸的电离常数为：Ka(HCN)＝6.2×10-10 mol/L、Ka(HF)＝6.8×10-4 mol/L、Ka(CH3COOH)＝1.8×10-5 mol/L、Ka(HNO2)＝6.4×10-6 mol/L。物质的量浓度都
选出下列语句与原文书写完全一致的一项是 ( ) （2分） A．既加冠，益暮圣贤之道。 B．衔觥赋诗，以乐其志。无怀氏之民欤?葛天氏之民欤?
公元前217年，某商人在宛(今河南南阳)交易时使用蚁鼻钱(楚国货币)，被当地官府依据《金布律》处罚。这表明 A．秦半两钱过重使用不便
After a few weeks in hospital, the patient is ________ getting over from his operation. A. actually B. gradually C. practically D. quietly
After the terrorist attack last month, anyone at the airport_______ heavy bags, bottles of liquid, or whatever, could be stopped and questioned by the police． A．seen carrying
下列实验操作或方法不能达到实验目的的是实验目的实验操作或方法 A分离苯和水分液 B从海水中提取淡水蒸馏 C提取碘水中的碘用酒精萃取 D分离硝
以下可能属于捕食关系的是 （ ） A．成年鲈鱼以幼年鱼为食 B．野兔
Everybody likes her because she is so honest a person that she ____ all the people around． A．is on good terms with B．get on well with C
