A:向石灰水中通入过量CO2: CO2+ O H —= HCO3 —
B:Na2O加入盐酸中:O2-+2H+=H2O
C:将少量H2SO4溶液滴加到Ba(OH)2溶液中H++SO42-+OH—+Ba2+=BaSO4↓+H2O
D:将铁粉加入到AgNO3溶液中Fe+Ag+=Ag+Fe2+
27÷3=____
36÷4=____
Look, read and choose. 选择画线词语的对应词,将序号写在括号里。
A. father
B. brother
C. grandma
D. man
E. student
⒈This is not a teacher. She's a ____.
⒉This is not a woman. He's a ____.
⒊This is not my grandpa. She's my ____.
⒋This is not my sister. He's my ____.
⒌This is not my mother. He's my ____.
“最美人物”眼下不仅成为不折不扣的网络热词,而且成为人们广泛学习的楷模。而在新时代文明社会的建设中,要更好地传递“最美人物”身上的正能量,我们必须( )①从身边小事做起,只对自己负责 ②培养高度的社会责任感③积极承担责任,不言代价与回报 ④学会热心公益、服务社会
某同学利用暑假去北京旅游,他想知道北京的位置,应该选择( )