CREATE TABLE "electrochemistry" (
  "element" text,
  "group" real,
  "period" real,
  "reaction" text,
  "potential" text
);

Question: Which potential's period 5 is 4 and has an element of antimony?
SQL: SELECT "potential" FROM "electrochemistry" WHERE "period"=5 AND "element"='antimony';

Question: Which lowest period's element is ruthenium?
SQL: SELECT MIN("period") FROM "electrochemistry" WHERE "element"='ruthenium';

Question: Which highest period's element is platinum?
SQL: SELECT MAX("period") FROM "electrochemistry" WHERE "element"='platinum';