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用磺基水杨酸法测定微量铁。称取 0.2160 g 的 NH 4 Fe ( SO 4 ) 2 • 12H 2 O 溶于水稀释 至 500 mL ,得铁标准溶液。按下表所列数据取不同体积标准溶液,显色后稀释至相同体积, 在相同条件下分别测定各吸光值数据如下: V /mL 0.00 2.00 4.00 6.00 8.00 10.00 A 2.00 0.165 0.320 0.480 0.630 0.790 取待测试液 5.00 mL ,稀释至 250 mL 。移取 2.00 mL ,在与绘制标准曲线相同的条件下 显色后测其吸光度得 A = 0.500 。用标准曲线法求试液中铁含量(以 mg/mL 表示)。已知 M [NH 4 Fe ( SO 4 ) 2 • 12H 2 O] = 482.178 g/mol 。
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【单选题】The word 'charity' in the last line but one refers to______.
A.
Cancer Chat.
B.
CancerHelp UK.
C.
TV's Casualty.
D.
Cancer Research UK.
【多选题】The ways to do charity work without breaking the bank include ____ .
A.
donate some old items
B.
donate blood
C.
volunteer time
D.
purchase from companies with a charitable model
【多选题】What does the word “charity” mean to you? ( more than one answer )
A.
Providing help or relief to the poor and needy.
B.
Benevolence or generosity toward others and toward humanity.
C.
An organization that facilitates charity benefiting people in need.
D.
The act of giving our money, time or resources to others without expecting a reciprocation or a direct return.
【多选题】The ways to do charity work without breaking the bank include ______ .
A.
donating some old items
B.
donating blood
C.
volunteering time
D.
purchasing from companies with a charitable model
【简答题】Word Bank cop n. 警察 hijack v. 劫机 Milan 米兰 (意大利城市)
【简答题】Word Bank return n. 利润;收益 vocational a. 职业的 mismatch n. 不匹配
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