问题:在规定条件下的固体或半固体石油产品达到一定流动性时的最低温度叫()A、熔点B、滴点C、软化点...
Monday, April 14, 2025
Saturday, May 27, 2023
Saturday, September 10, 2022
Tuesday, September 13, 2022
问题:需配制10%(g/mL)NH4Cl溶液1000毫升,现有30%(g/mL)和5%(g/mL)NH4Cl溶液两种,应如何配制?...
Wednesday, December 14, 2022
Tuesday, September 13, 2022
问题:石油产品粘度指数的计算是按()来计算的。A、50℃和100℃运动粘度B、100℃运动粘度C、50℃运动粘度D、40℃和100℃运动粘度...
Thursday, November 23, 2023
问题:用托盘天平称取一定数量的试样,砝码应放在左边的托盘上。...
Wednesday, October 25, 2023
Thursday, August 29, 2024
Saturday, September 10, 2022
Friday, September 16, 2022
Tuesday, September 13, 2022
问题:化验室蒸馏低沸点易燃液体时,应采用密闭式电热管的()或(),尽量避免用()。...
Tuesday, February 14, 2023
问题:把3.65克氯化氢溶解于水里制成1升溶液,这种盐酸的物质的量浓度为()A、0.1mol/LB、0.2mol/LC、0.8mol/LD、0.4mol/L...
Saturday, May 27, 2023
Saturday, March 9, 2024
问题:用以检定其它砝码和天平的具有较高精度的砝码称()。...
Tuesday, September 13, 2022
Saturday, March 9, 2024
问题:在电解含有Ag离子的溶液时.欲使阴极析出1摩尔的银。问需通入的电量是多少?已知每个电子的电荷电量是1.602×10-19库仑,阿伏伽德罗常数NA为6.023×1023...
Sunday, December 31, 2023
问题:90号车用汽油即表明该汽油辛烷值等于或大于()。...
Tuesday, September 13, 2022
Tuesday, September 13, 2022