挑战习题
1/5单选题
难度:

1.

阳光牌小包装“脱氧剂”成分为Fe粉、活性炭及少量NaCl、水。使用一段时间后,其中的Fe粉会转变成Fe2O3而变质。某化学兴趣小组欲探究使用过的阳光牌“脱氧剂”的变质程度(已变质的Fe粉占变质前Fe粉的质量分数),设计并进行如下探究过程。步骤(1):取食品包装袋中的阳光牌“脱氧剂”一袋,将里面的固体溶于水,过滤、洗涤、干燥滤渣。步骤(2):取步骤(1)中的滤渣8.0 g,加入足量的稀H2SO4与滤渣充分反应,过滤、洗涤、干燥得固体1.2 g。步骤(3):取步骤(2)中的滤液,加入足量的NaOH溶液,得到的固体经洗涤后转移到坩埚中,充分加热、冷却、称量,得到8.0g Fe2O3(注:滤液中的Fe元素已全部转化为Fe2O3)。该“脱氧剂”的变质程度为


A

60%

B

70%

C

40%

D

50%

提示1:
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提示2:
PHA+OC4wIGfmu6TmuKPkuK1GZeWSjEZlPHN1Yj4yPC9zdWI+TzxzdWI+Mzwvc3ViPuS4pOenjeeJqei0qOeahOaAu+i0qOmHj+S4ujguMCBnLTEuMiBnID0gNi44IGc8L3A+
提示3:
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提示4:
PHA+PGltZyBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzEwL0UyL3JCQUNGRk1TOFdlQ1hWUzBBQUFPNjNNSzVLdzY1MS5wbmciIGRhdGEtY2tlLXNhdmVkLXNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvMTAvRTIvckJBQ0ZGTVM4V2VDWFZTMEFBQU82M01LNUt3NjUxLnBuZyIgaGVpZ2h0PSI3NyIgd2lkdGg9IjI3MCI+PC9wPg==
正确答案:RA==
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