⑵ 0.0400 M Na₂C₂O₄ K_a2(H₂C₂O₄) = 5.42 × 10^-5

⑴計算 EDTA 溶液之莫耳濃度。

⑵礦泉水中含的 CaCO3濃度（ppm）。

⑶礦泉水中含的 MgCO3濃度（ppm）。 （註：原子量 Mg = 24.3, Ca = 40.1, C = 12.00, O = 16.00）

⑴ 0.0400 M Na3PO4, Ka3(H3PO4) = 4.5 × 10-13

⑶ 40.0 mL 的 0.1250 M NH3 與 20.0 mL 的 0.100 M HCl 混合溶液 Ka(NH4+) = 5.7 × 10-10

⑷ 0.0240 M H2C2O4（oxalic acid）及 0.0360 M Na2C2O4混合溶液

⑸ 0.0400 M C2H4(NH3+ Cl- )2 Ka1(NH3C2H4NH3+2) = 1.42 × 10-7

⑴計算氫氧化鋇莫爾濃度。

⑵如果重量與體積的標準偏差分別為±0.3mg 及±0.02 mL，計算莫爾濃度 的標準偏差並以有效數字表示氫氧化鋇莫爾濃度及標準偏差。

一、Translate the following English passage into Chinese.（25 分） British Prime Minister Theresa May is calling on her fractious Conservative Party to unite on a Brexit strategy and help her negotiate a separation agreement with the European Union. May told her party’s annual conference Wednesday in Birmingham they are entering the “toughest phase of the negotiations.” Britain will leave the 28-nation bloc on March 29 and talks to reach a divorce deal have stalled. An influential pro-Brexit faction within May’s party led by former foreign minister Boris Johnson is urging her to be firm and exit the European Union without a deal if necessary. The faction opposes May’s proposal for Britain to adhere to EU trade rules after it leaves, calling instead for a clean break. May did not rule out leaving without an agreement, but said doing so “would be a bad outcome for the U.K. and the EU.”