小丽午餐时买了一份清炒菠菜和一份豆腐肉片汤,但有同学告诉她菠菜不能与豆腐同食.

题型:问答题

问题:

小丽午餐时买了一份清炒菠菜和一份豆腐肉片汤,但有同学告诉她菠菜不能与豆腐同食.

[发现问题]菠菜为什么不能与豆腐同食?

[查阅资料]a.制作豆腐需要加入石膏(主要成分:CaSO4);

b.菠菜中含有草酸、草酸盐等成分;

c.草酸钙是一种既不溶于水也不溶于醋酸的白色固体,是诱发人体结石的物质之一.

[提出猜想]菠菜与豆腐同食可能会产生人体不能吸收的沉淀物.

[设计实验]

实验步骤实验现象实验结论
①将菠菜在少量开水中煮沸2~3min,取l~2mL滤液于试管中,并滴加少量______溶液.产生白色沉淀有草酸钙生成
②在步骤①的沉淀物中加入过量醋酸沉淀部分溶解,且产生气泡被溶解的沉淀一定不是______

______

[发现新问题]被溶解的沉淀是什么?产生的气体又是什么?于是她又设计如下实验进一步探究:

实验步骤实验现象实验结论
③将步骤②产生的气体通入______

______中

______

______

产生的气体是______;

步骤②被溶解的沉淀是碳酸钙

[反思与应用]家庭中常常将菠菜放在开水中烫过后再烹饪,其目的是______.

考点:设计实验和科学探究盐的性质
题型:问答题

张力性气胸的急救处理首先应该

A.剖胸探查

B.立即排气解除胸膜腔的高压状态

C.气管内插管辅助呼吸

D.输血、输液治疗休克

E.气管切开

题型:问答题

根据有关法律法规,债的发生根据不包括( )。

A.合同
B.侵权
C.不当得利
D.提存

题型:问答题

消费信用是( )。

A.企业相互之间提供的信用

B.银行对企业提供的信用

C.国家向居民举债而产生的信用

D.工商企业或银行以商品或货币的形式向个人消费者提供的信用

题型:问答题

An airplane engine manufacturer developed a new engine model with safety features lacking in the earlier model, which was still being manufactured. During the first year that both were sold, the earlier model far outsold the new model; the manufacturer thus concluded that safety was not the customers’ primary consideration.
Which of the following, if tree, would most seriously weaken the manufacturer’s conclusion

A.Both private plane owners and commercial airlines buy engines from this airplane engine manufacturer.

B.Many customers "consider earlier engine models better safety risks than new engine models, since more is usually known about the safety of the earlier models.

C.Many customers of this airplane engine manufacturer also bought airplane engines from manufacturers who did not provide additional safety features in their newer models.

D.The newer engine model can be used in all planes in which the earlier engine model can be used.

E.(E) There was no significant difference in price between the newer engine model and the earlier engine model.

题型:问答题

个体诊所不得配备常用药品和急救药品以外的其他药品,常用药品和急救药品的范围和品种的规定部门是()

A.国家药品监督管理局会同卫生部

B.所在地的县级卫生行政部门和同级药品监督管理部门

C.所在地的县级卫生行政部门会同同级药品监督管理部门

D.所在地的市级卫生行政部门和同级药品监督管理部门

E.所在地省级卫生行政部门会同同级药品监督管理部门

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