A.Having been passed
B.Having passed
C.As he had been passed
D.Since he has been passed

A.When
B.While
C.Although
D.Because

A.due to the fact
B.owing to
C.seeing that
D.as

A.Since
B.While
C.For
D.With

A.in order to
B.not to
C.so that
D.so as not to

A.HCO3-.
B.Al3+.
C.AlO2-.
D.Na3AlF6.

A.axit axetic.
B.etilen.
C.đimetylete.
D.fomanđehit.

A.Fe(NO3)3, Zn(NO3)2, AgNO3.
B.Fe(NO3)3, Fe(NO3)2, Zn(NO3)2.
C.Fe(NO3)3, Fe(NO3)2, AgNO3.
D.Fe(NO3)2, Zn(NO3)2, AgNO3.

A.2
B.3
C.0
D.1

A.NaOH, Na2CO3, FeCl3.
B.KOH, K2CO3, FeCl3.
C.KHCO3, K2CO3, FeCl3.
D.KOH, K2CO3, Fe2(SO4)3.