题干

将一块银白色的金属钠放在空气中会发生一系列的变化:表面迅速变暗→“出汗”→变成白色固体(粉末),下列有关叙述不正确的是(   )

A:表面迅速变暗是因为钠与空气中的氧气反应生成了氧化钠

B:“出汗”是因为生成的氢氧化钠吸收空气中的水蒸气在表面形成了溶液

C:最后变成碳酸钠粉末

D:该过程的所有化学反应均为氧化还原反应

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D

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Happiness begins from appreciation

    If you are feeling that life just cannot be any worse for you, it can be challenging to think positive. When stressed, depressed, upset or otherwise in a negative state of mind because you are aware that misfortune keeps occurring, it is important to shift those negative thoughts to something positive____

    It is often very hard to think positive when so many things are negative, but be sure that someone, somewhere is worse off than you____ If you start with one small, positive thing and appreciate it during the course of your day, you will begin to move into a more positive situation and people will start showing up in your life. With appreciation, you will find that over time, you will change your outlook and choose to be happy, regardless of the events around you____

    Begin and end each day with a “Thank you for this wonderful, glorious day!”

    When you see the rise of gas prices, say “I am so glad to have a vehicle in which to get around.”

    When your boss is too hard on you, say “I am grateful for my job as I know that many don't have one.”

    If you are having health problems, be grateful for what does work: “I really do appreciate it that my eyes see, my ears hear, my mouth tastes, my legs walk, my arms lift and my mind thinks and everything else works.”

    Write down what you're grateful for each day. In moments when you're feeling really down, read loud what you wrote previously____If you practice this regularly, you will find your list getting longer and longer.

    The key is to move yourself into a positive thought and keep it there long enough to make it a moment of appreciation____

A. This will certainly help uplift your spirits.

B. If not, you will only attract more misfortune.

C. It is of great importance to learn to be grateful.

D. The more you appreciate, the happier you'll be.

E. You have made some achievements in your career.

F. Here are a few common examples for you to practice.

G. You can choose to think differently by beginning with the smallest of steps.