A:加水稀释到原体积的10倍,溶液的pH=4
B:加水稀释,溶液中 c(CHCOO−)c(CH3OOH)⋅C(OH−) 不变,n(OH﹣)增大
C:加入10 mL pH=11的NaOH溶液,所得混合液的pH=7
D:加入少量醋酸钠固体,则平衡CH3COOH⇌CH3COO﹣+H+逆向移动,K变小
化简2-3=____
如图所示,E板上发射的电子初速度为零,两电源的电压分别为45V、30V,A、B两板上有小孔OA、OB,则电子经过OA、OB孔以及到达C板的动能分别为:EkA=____eV,EkB=____eV,EkC=____eV.
如果等腰三角形的两边长是25cm和10cm,那么它的周长是( )
Do you like watching TheVoiceofChina? If you like it, you may know Zhang Lei.He ____(win) first place in TheVoiceofChinaIV.He comes from Heilongjiang.He was good at singing when he was young.He likes playing the g____He can sing many songs.People feel very ____(relax) when they hear Zhang Lei's songs.He wants to be a ____(sing) like Lao Lang in the f____ Do you like his songs?