题干

已知硫酸亚铁溶液中加入过氧化钠时发生反应:4Fe2+ + 4Na2O2 + 6H2O=== 4Fe(OH)3↓+ O2↑+8 Na+,则下列说法正确的是

A:该反应中Fe2+是还原剂,O2、Fe(OH)3均为氧化产物

B:4 mol Na2O2在反应中共得到8 NA个电子

C:标准状况下,每生成11.2 LO2,则有4 mol Na2O2被还原

D:反应过程中可以看到白色沉淀转化为灰绿色再转化为红褐色沉淀

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A

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    With the cold weather season rapidly approaching, caring for dry skin may become more challenging. Here are some tips on how to protect your skin and keep it healthy throughout the colder months of the year.

    ____ 

    Avoid harsh(刺激性的) cleansers containing sulfates or alcohol, and choose a gentle cleanser. Harsh cleansers may disrupt the PH balance of your skin and cause dryness.

    Switch to a face oil

    ____ In order to avoid dryness, rub about 3 to 5 drops of oil the palm of your hands and then gently pat it into the skin. Face oils offer the benefit of conditioning the skin and protecting it from the cold air.

    Exfoliate(去死皮)

    Exfoliating is very important because it helps to get rid of dead skin cells and encourages skin cell renewal.____ However, especially when the skin is feeling extra dry, it is important to use a gentle product and not to overdo it.

    ____ 

    If you don't feel thirsty and struggle with taking in enough liquids, try to drink tea, sweetened with a little raw honey. Dehydrated skin cells have a slower turnover rate, which results in dull skin and more visible fine lines.

    ____ The most advantage is that you will spend the cold season with comfort and confidence.

A. Drink plenty of water

B. Eat homemade soups

C. Use mild facial cleansers

D. Follow the above tips, you may own nice skin and look better.

E. Here are three of the most common example of skin discomfort.

F. After cleansing your face, your skin still takes the risk of dryness.

G. Moreover, dead skin cells won't allow your face oil to enter the skin deeply.