【单选题】根据国家药品编码本位码编制规则,本位码的组成不包括
【单选题】将浓度为0.40mol·L -1 HAc溶液与0.20mol·L -1 NaOH溶液等体积混合,其溶液的pH为(K a =1.8×10 -5 )()。
【单选题】将浓度为5 mol·L?1NaOH溶液100 mL,加水稀释至500 mL,则稀释后的溶液浓度为
【简答题】Ohm's Law states that the voltage across a resistor is the current flowing through the resistor.A. equal
to B. directly
proportional to C. inversely
proportional to D. different
from
【单选题】Ohm ’ s Law states that the voltage across a resistor is _____ the current flowing through the resistor.
B.
directly proportional to
C.
inversely proportional to