If you don't have much time, you have a pet. [ ]
A. mustn't
B. shouldn't
C. must
D. can't
答案:B
下列离子反应方程式正确的是( )
A.氯气与水反应:Cl2+H2O=2H++Cl -+ClO-
B.Ba(OH)2溶液与稀硫酸反应:Ba2++OH -+H++SO42-=BaSO4↓+H2O
C.钠与水反应:2Na+2H2O=2Na++2OH -+H2↑
D.制备 Fe(OH)3胶体的反应:Fe3++3H2O=Fe(OH)3↓+3H+
大量心包积液可有( )
A.奇脉B.重搏脉C.交替脉D.水冲脉E.短绌脉