试题与答案

已知同温、同压下,气体的相对分子质量越小密度就越小(相对原子质量:H-1C-l2

题型:选择题

题目:

已知同温、同压下,气体的相对分子质量越小密度就越小(相对原子质量:H-1  C-l2  N-14 O-16   S-32),则下列气体中密度最小的是(  )

A.NH3

B.CO

C.SO2

D.CO2

答案:

相对分子质量最小的物质密度最小;

A、氨气的相对分子质量=14+3=17;

B、一氧化碳的相对分子质量=12+16=28;

C、二氧化硫的相对分子质量=32+(16×2)=64;

D、二氧化碳的相对分子质量=12+16×2=44.

故选A.

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Sydney Airport International Terminal-Arrival Area

SPECIALTY RETAIL

Newslink: Two separate Newslink stores cater to all your reading needs including newspapers, magazines and the latest bestsellers.

Downtown Duty Free: Make sure you shop at Downtown Duty Free for great savings on a range of items including perfume, alcohol, skincare and cigarettes. It’s your last chance before customs.

Beach Culture: A must for those into the Latest in beach clothing. Top surfer street and fashion labels including Mambo, Stussy and Quicksilver, including children’s sizes

DINING

Blue Sky Cafe: Speedy service leaves you time to keep an eye on the arrivals gate. Fresh milk, coffee, lemon juice, beer, Whisky, ice-cream, soda water, cakes and dumplings are on sale.

Macdonald’s: hamburgers, fries, pancakes, toasted potatoes, muffins, Pepsi, coca-cola and chocolates-all your family favorites. Breakfast served until 10:30.

SERVICES

ATM: ATMs are conveniently located throughout Arrival and Departures. Dollars, pounds and francs and RMB are all available.

Vodafone Rentals: This communications center offers the very latest technology for mobile phone rentals, sales and serving.

小题1:Where is the passage likely to appear?

A.A morning newspaper.

B.A monthly magazine.

C.A geography book.

D.An official guide.小题2:The underlined phrase “cater to” probably means ________.

A.satisfy

B.afford

C.support

D.help小题3:You may have better choices to deal with _________.

A.your hunger problem in Blue Sky Cafe and your thirsty problem in Macdonald’s

B.your thirsty problem in Blue Sky Cafe and your hunger problem in Macdonald’s

C.your hunger and thirsty problems in the Blue Sky Cafe

D.your hunger and thirsty problems in the Macdonald’s小题4:At Beach Culture you can probably buy __________.

A.newspapers and magazines

B.skincare and cigarettes

C.adult cotton T-shirts

D.fresh juice and breakfast roils

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题型:单项选择题

男孩,5岁,洗澡时发现右腹部包块1个月。查体:右上腹包块,肋缘下3cm可及,质软。超声显示右肾严重积水,肾皮质厚度0.5cm。患儿不能配合静脉肾盂造影检查。

在镇痛麻醉下经超声引导右肾盂穿刺造瘘及造影显示肾盂输尿管连接部狭窄,造瘘管引流尿量每天约400ml,引流尿的比重为1.015。最合理的处理是().

A.右肾切除术

B.永久性右肾盂造瘘术

C.右肾及输尿管全切除术

D.拔除肾造瘘管维持原状

E.右肾盂-输尿管连接部成形术

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