NaOH滴定H<sub>3</sub>PO<sub>4</sub>(pK<sub>a1</sub>~pK<sub>a3</sub>分别为2.12,7.20,12.36)至产物为Na<sub>2</sub>HPO<sub>4</sub>,应选用的指示剂是()
A、甲基橙
B、甲基红
C、酚酞
D、百里酚酞
A、甲基橙
B、甲基红
C、酚酞
D、百里酚酞
A、测定H<sub>2sub>C<sub>2sub>O<sub>4sub>·H<sub>2sub>O摩尔质量时,H<sub>2sub>C<sub>2sub>O<sub>4sub>·H<sub>2sub>O失水 B、用NaOH标准溶液滴定HCl溶液时,滴定管内壁挂有水珠 C、滴定前用标准溶液荡洗了锥形瓶 D、用于标定溶液的基准物质吸湿
A、HCl滴定NaCN(HCN:pK<sub>asub>=9.21) B、HCl滴定苯酚钠(苯酚:pK<sub>asub>=10.00) C、NaOH滴定吡啶盐(吡啶:pK<sub>bsub>=8.77) D、NaOH滴定甲胺盐(甲胺:pK<sub>bsub>=3.37)
A、NaOH+Na<sub>2sub>CO<sub>3sub> B、NaOH+NaHCO<sub>3sub> C、NaHCO<sub>3sub>+Na<sub>2sub>CO<sub>3sub> D、Na<sub>2sub>CO<sub>3sub>
A、NaOH、O<sub>2sub>、H<sub>2sub> B、NaOH、O<sub>2sub>、Cl<sub>2sub> C、NaOH、Cl<sub>2sub>、H<sub>2sub> D、NaOH、O<sub>2sub>
A、H<sub>2sub>→C<sub>2sub>H<sub>4sub>→C<sub>3sub>H<sub>6sub>→C<sub>2sub>H<sub>2sub>→CO B、H<sub>2sub>→CO→C<sub>2sub>H<sub>4sub>→C<sub>3sub>H<sub>6sub>→C<sub>2sub>H<sub>2sub> C、H<sub>2sub>→C<sub>2sub>H<sub>4sub>→C<sub>3sub>H<sub>6sub>→CO→C<sub>2sub>H<sub>2sub> D、CO→H<sub>2sub>→C<sub>2sub>H<sub>4sub>→C<sub>3sub>H<sub>6sub>→C<sub>2sub>H<sub>2sub>
A、HCOOH(Ka=1.77×10
A、与足量的NaOH溶液共热后,再通入足量CO<sub>2sub> B、与足量的NaOH溶液共热后,再加入适量H<sub>2sub>SO<sub>4sub> C、与稀H<sub>2sub>SO<sub>4sub>共热后,加入足量的NaOH溶液 D、与稀H<sub>2sub>SO<sub>4sub>共热后,加入足量的Na<sub>2sub>CO<sub>3sub>溶液
A、Na<sub>2sub>CO<sub>3sub> B、NaHCO<sub>3sub> C、NaOH D、NaOH+Na<sub>2sub>CO<sub>3sub>
A、NaOH,Mg(OH)<sub>2sub>,HCl B、BaCl<sub>2sub>,AgNO<sub>3sub>,HNO<sub>3sub> C、CaCl<sub>2sub>,K<sub>2sub>CO<sub>3sub>,HCl D、CuSO<sub>4sub>,NaOH,H<sub>2sub>SO<sub>4sub>
A、K<sub>Psub>不变,平衡时的N<sub>2sub>和H<sub>2sub>的量将增强,而NH<sub>3sub>的量减少 B、K<sub>Psub>不变,平衡时的N<sub>2sub>、H<sub>2sub>、NH<sub>3sub>的量均不变 C、K<sub>Psub>不变,平衡时的N<sub>2sub>和H<sub>2sub>的量将减少,而NH<sub>3sub>的量增加 D、K<sub>Psub>增加,平衡时的N<sub>2sub>和H<sub>2sub>的量将减少,而NH<sub>3sub>的量增加