题干

Na2O2具有强氧化性,H2具有还原性,某同学根据氧化还原反应的知识推测Na2O2与H2能发生反应。为了验证此推测结果,该同学设计并进行如下实验。

I.实验探究

步骤1:按如图所示的装置组装仪器(图中夹持仪器已省略)并检查装置的气密性,然后装入药品。

步骤2:打开K1、K2,在产生的氢气流经装有Na2O2的硬质玻璃管的过程中,未观察到明显现象。

步骤3:进行必要的实验操作,淡黄色的粉末慢慢变成白色固体,无水硫酸铜未变蓝色。

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    Housework is a frequent source of disputes (争论) between lazy husbands and their hard-working wives, but women have been warned not to expect men to pull their weight any time soon.

    A study from Oxford University has found that men are unlikely to be doing an equal share of housework before 2050. Mothers, the researchers warned, will continue to shoulder the burden of childcare and housework for the next four decades, largely because housework such as cleaning and cooking is still regarded as “women's work”.

    The gap between the amount of time men and women spend on housework has narrowed slowly over the past 40 years. But it will take another four decades before true housework equality (平等) is achieved, the study concluded.

    The research found that in the Nordic countries, the burden of housework is shared more equally between men and women. In the UK, women spend an average of four hours and forty minutes each day on housework, compared with two hours and twenty-eight minutes for men. This is an improvement from the 1960s, when British women typically spent six hours a day on housework, while men spent just 90 minutes every day.

    But progress towards housework equality appears to be slowing in some countries. Dr Oriel Sullivan, a research reader from Oxford's Department of Sociology, said, “we've looked at what is affecting the equality in the home, and we have found that certain tasks seem to be given according to whether they are viewed as ‘men's work' or ‘women's work'.”

    Dr Sullivan said cultural attitudes taught at school may be responsible for the views of housework. “At school it is much easier for a girl to be a tomboy, but it is much more difficult for a boy to enjoy baking and dancing,” she said.