题目

—Where is the map? —It'syourroom. A . on; parent's B . in; parents's C . in; parents' D . on; parents' 答案：C3．判断下列各组离子能否大量共存①Ca2+   Na+   CO32-     NO3-     ②Ca2+   Na+   SO42-    NO3-③H+     K+    Cl-   OH-        ④NH4+   K+    OH-      SO42-⑤H+     K+    CO32-   SO42-      ⑥Na+    K+    CO32-     OH-．