用部分已风化的H<sub>2</sub>C<sub>2</sub>O<sub>4</sub>·2H<sub>2</sub>O作为基准物质用于标定氢氧化钠的浓度,则氢氧化钠的浓度将()
A、偏高
B、偏低
C、无影响
D、不能确定
A、偏高
B、偏低
C、无影响
D、不能确定
A、C<sub>2sub>H<sub>3sub> B、C<sub>2sub>H<sub>4sub> C、C<sub>2sub>H<sub>2sub> D、CH<sub>2sub>
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、H<sub>1sub>、H<sub>2sub>A、H<sub>2sub>B、H<sub>3sub> B、H<sub>1sub>、H<sub>2sub>A、H<sub>2sub>B、H<sub>3sub>A C、H<sub>2sub>A、H<sub>2sub>B、H<sub>3sub>、H<sub>4sub> D、H<sub>2sub>A、H<sub>2sub>B、H<sub>3sub>A、H<sub>4sub>
A、CH<sub>4sub>、CO、C<sub>2sub>H<sub>4sub>、C<sub>2sub>H<sub>6sub> B、CH<sub>4sub>、CO、C<sub>2sub>H<sub>4sub>、C<sub>2sub>H<sub>6sub>、C<sub>2sub>H<sub>2sub> C、CH<sub>4sub>、C<sub>2sub>H<sub>2sub>、C<sub>2sub>H<sub>4sub>、C<sub>2sub>H<sub>6sub> D、CO、CO<sub>2sub>、H<sub>2sub>、CH<sub>4sub>、C<sub>2sub>H<sub>4sub>、C<sub>2sub>H<sub>6sub>
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、C0<sub>2sub>和H<sub>2sub>0中的0就是产物中0<sub>2sub>的来源 B、C0<sub>2sub>被固定之后H<sub>2sub>0就被分解 C、H<sub>2sub>0在光下裂解就产生了C0<sub>2sub>固定所必需的有机物 D、0<sub>2sub>的释放和(CH<sub>2sub>0)的产生是两个相对独立的过程
A、△H<sub>1sub>〉△H<sub>2sub>,W<sub>1sub>〈W<sub>2sub> B、△H<sub>1sub>〈△H<sub>2sub>,W<sub>1sub>〉W<sub>2sub> C、△H<sub>1sub>=△H<sub>2sub>,W<sub>1sub>〈W<sub>2sub> D、△H<sub>1sub>=△H<sub>2sub>,W<sub>1sub>〉W<sub>2sub>
A、△H<sub>1sub>〈△H<sub>2sub>,W<sub>1sub>〉W<sub>2sub> B、△H<sub>1sub>〉△H<sub>2sub>,W<sub>1sub>〈W<sub>2sub> C、△H<sub>1sub>〈△H<sub>2sub>,W<sub>1sub>〈W<sub>2sub> D、△H<sub>1sub>〉△H<sub>2sub>,W<sub>1sub>〉W<sub>2sub>
A、c(FeSO<sub>4sub>)=c(H<sub>2sub>C<sub>2sub>O<sub>4sub>) B、3c(FeSO<sub>4sub>)=c(H<sub>2sub>C<sub>2sub>O<sub>4sub>) C、2c(FeSO<sub>4sub>)=c(H<sub>2sub>C<sub>2sub>O<sub>4sub>) D、c(FeSO<sub>4sub>)=2c(H<sub>2sub>C<sub>2sub>O<sub>4sub>)