根据现行部颁规定,材料采购及保管费率为()。
A.0.7%
B.2.5%
C.3%
D.4%
参考答案:C
标准状况下,向100mL 3mol•L-1的NaOH溶液中缓缓通入4.48L CO2 气体,充分反应后溶液中离子浓度大小排列顺序正确的是( )
A.c(Na+)>c(CO 2-3)>c(HCO -3)>c(OH-)>c(H+)
B.c(Na+)>c(CO 2-3)=c(HCO -3)>c(OH-)>c(H+)
C.c(Na+)>c(HCO -3)>c(OH-)>c(CO 2-3)>c(H+)
D.c(Na+)>c(HCO -3)>c(CO 2-3)>c(OH-)>c(H+)
Can I open the window? [ ]
A. yes. I can
B.yes. you can
C. no. you can't
D. sorry. I can't