问题 填空题

下图是实验室常用的实验装置,请回答下列问题。

(1)写出仪器的名称a                  、b                

(2)用上述装置组装实验室制取和收集氢气的一组仪器组合是           (填装置代号字母),若用F进行排空气法收集氢气,则气体应从      口进入(填c或d)。请写出制取氢气的化学方程式                               

(3)若某同学用C装置收集一瓶较纯净氧气,当观察到               时开始收集。

答案

(1)锥形瓶 铁架台(2)A    C 或E 或F   d    Zn+ H2SO4 = ZnSO4 + H2

(3)气泡连续并均匀冒出或气泡连续冒出或大量气泡冒出

(1)根据实验室常见仪器,可知仪器的名称a 锥形瓶;b 铁架台;

(2)在实验室里,常用锌与稀硫酸反应来制取氢气,固液常温型的发生装置;氢气不溶于水,密度比空气小,选取收集装置;所以制取和收集氢气的一组仪器组合是:A 和 C( 或E 或F );氢气密度比空气密度小,若用F进行排空气法收集氢气,则气体应从 d 口进入;

锌与稀硫酸反应来制取氢气的反应方程式为:Zn+H2SO4=ZnSO4+H2↑;

(3)根据排水法收集气体时,导管口一开始冒气泡时,不宜立即收集,因为此时的气体中混有空气;当气泡连续、均匀冒出时,把导管口放在瓶口内开始收集气体;所以要收集一瓶较纯净氧气,当观察到气泡连续并均匀冒出 (或气泡连续冒出 或大量气泡冒出)时开始收集

单项选择题
单项选择题

It is not just Indian software and "business-process outsourcing" firms that are benefiting from the rise of the internet. Indian modern art is also on an upward spiral, driven by the aspirations of newly rich Indians, especially those living abroad, who use the internet to spot paintings and track prices at hundreds of gallery and auction websites. Prices have risen around 20-fold since 2000. particularly for prized names such as Tyeb Mehta and F.N. Souza.

There would have been "no chance" of that happening so fast without the internet, says Arun Vadehra, who runs a gallery in Delhi and is an adviser to Christie’s, an international auction house. He expects worldwide sales of Indian art, worth $ 200million last year, to double in 2006. It is still a tiny fraction of the $ 30 billion global art market, but is sizeable for an emerging market.

For newly rich--often very rich--non-resident Indians, expensive art is a badge of success in a foreign land." Who you are, and what you have, are on your walls," says Lavesh Jagasia, an art dealer in Mumbai. Indian art may also beat other forms of investment. A painting by Mr. Mehta that fetched $ 1.58 million last September would have gone for little more than $ 100 000 just four years ago. And a $ 22million art-investment fund launched in July by Osian’s, a big Indian auction house, has grown by 4.1% in its first two months.

Scant attention was paid to modern Indian art until the end of the 1990s. Then wealthy Indians, particularly those living abroad, began to take an interest. Dinesh Vazirani, who runs Saffronart, a leading Indian auction site, says 60% of his sales go to buyers overseas.

The focus now is on six auctions this month. Two took place in India last week; work by younger artists such as Surendran Naif and Shibu Natesan beat estimates by more than 70%. Sotheby’s and Christie’s have auctions in New York next week, each with a Tyeb Mehta that is expected to fetch more than $ 1 million. The real question is the fate of other works, including some by Mr. Souza with estimates of up to $ 600 000. If they do well, it will demonstrate that there is p demand and will pull up prices across the board. This looks like a market with a long way to run.

It can be inferred from the second paragraph that the recent rapid development of Indian modern art is closely associated with ()

A. economic boom

B. real estate

C. electronic element

D. international action