题干

化学实验中常将溶液或试剂进行酸化,下列酸化处理的措施正确的是(   )

A:检验溶液中是否含有SO32-时,用硝酸酸化后再加BaCl2溶液

B:为提高高锰酸钾溶液的氧化能力,用盐酸将高锰酸钾溶液酸化

C:检验溶液中是否含有Fe2+时,用硝酸酸化后,加KSCN溶液

D:检验溶液中是否含有SO42-时,用盐酸酸化后,加BaCl2溶液

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D

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    About 7 million people over the age of 65 have been diagnosed with depression, and many more could be suffering. It is high time that you learned how to know the signs and help them. Depression is a big problem for seniors, especially those who are lack of care and attention. Older people are much more likely to be alone, socially isolated(孤立的) or feel a lack of purpose. Sometimes older people have a much more difficulty time admitting mental health problems. Many times, the link between depression and physical illness is much stronger.

    The elderly don't like to express sadness the way that young people do. Older people who are depressed may have more physical troubles and may pay more attention to them. Depression may result from early memory loss and meanwhile, depression will make a person forget more and faster. A patient with early memory loss and depression really needs to be treated for the depression to slow the memory loss. A mood change is also a sign of depression. If a previously calm person becomes increasingly annoyed, or a previously clean person no longer bothers to shower or clean up, that person should be considered.

    Don't tell older adults that you think they may be depressed, as older adults --- particularly men–see depression as a weakness. What you should do is tell them you're worried about their health. Tell them they seem to be out of sorts.

    Say you just want to check with the doctor to see what's going on. Once you've used physical symptoms to get that person to agree to a check-up, mention your fear to the doctor and allow the doctor to approach the subject of depression with the patient.