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问题 填空题

碳是构成物质种类最多的一种元素，许多物质都与我们的生活息息相关．

①根据表中提供的信息，填写有关含碳物质的对应特性

物质用途金刚石切割玻璃石墨作电极活性炭净水
对应特性硬度大____________
②金刚石、石墨和碳60都是由碳元素形成的单质，这些物质互称为碳元素的______．

③CO2是宝贵的碳氧资源．CO2和H2在一定条件下可合成甲酸（HCOOH），此反应中CO2与H2的分子个数比为______，若要检验1%甲酸水溶液是否显酸性，能选用的有______（填字母序号）

a．无色酚酞溶液b．紫色石蕊溶液c．pH试纸

④化石燃料有煤、石油和天然气，它们都属于______（填“可再生”或“不可再生”）能源．天然气最主要成分是甲烷，完全燃烧生成二氧化碳和水，该燃烧反应的化学方程式为______．从下表数据分析，与煤相比，用天然气作燃料的优点是______．

1g物质完全燃烧甲烷碳
产生二氧化碳的质量/g2.753.67
放出的热量/kJ5632

答案

①由于石墨具有导电性，可用作电极；由于活性炭有吸附性，可用于净水．

②金刚石、石墨和碳60都是由碳元素形成的单质，这些物质互称为碳元素的同素异形体．

③CO2和H2在一定条件下可合成甲酸（HCOOH），反应的方程式是：CO2+H2

一定条件下
.
HCOOH，此反应中CO2与H2的分子个数比为1：1，若要检验1%甲酸水溶液是否显酸性，可选用紫色石蕊溶液、pH试纸检验．

④化石燃料有煤、石油和天然气，它们都属于不可再生；甲烷燃烧生成了二氧化碳和水，反应的方程式是：CH4+2O2

点燃
.
CO2+2H2O；由表中的数据可知，等质量的天然气和煤完全燃烧，天然气燃烧产生二氧化碳的质量小于煤，放出的热量高于煤．

故答为：①导电性；吸附性；②同素异形体；③1：1；bc．④不可再生；CH4+2O2

点燃
.
CO2+2H2O；等质量的天然气和煤完全燃烧，天然气燃烧产生二氧化碳的质量小于煤，放出的热量高于煤．

选择题

小刚想在一棵荔枝树上结出几种不同口味的荔枝，他采用的方式是[ ]

A．嫁接

B．扦插

C．压条

D．组织培养
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单项选择题

Solar Trophy: Call to Competitors


The Solar Trophy, inaugurated one year ago with only three boats completing an ocean crossing from Cape Town to Hobart, has established itself as a truly unique event in the calendar of ocean racing. Each of the 20 meter boats was powered only by the energy provided by solar panels. The race was won by a four-man team captained by Hans Larssen from Stockholm aboard lcarus 2.
Following the success of the first race, the race committee has decided to hold the event every three years. Teams wishing to participate in the next edition of the race are hereby invited to submit their applications. The full application package and race regulations can be downloaded from the Solar Trophy website (www://solartrophy.org).
The organizers would like to remind applicants that only solar-powered yachts are authorized to compete and that all vessels must correspond to the specifications in the race regulations. If you have additional questions regarding the application process, please contact Carmen Johannsen by e-mail at C.Johannsen@solartrophy.org or by telephone on 04 95 35 47.
To: Hank Martin
From: Anna Sabiani
Date: August 23 11:47
Subject: Promotional opportunity
Hi, Hank,
I am forwarding the press release about the Solar Trophy that I mentioned to you this morning. I met Bill Bradley, the race coordinator, at the solar energy conference in Manila where he was giving a presentation about the event. I understand from him that the first race was a huge success and generated enormous media coverage both in traditional media and on the Internet. For the next edition of the race he is expecting applications from as many as twenty yachts from seven different countries, including Japan. He suggested that we might like to sponsor one of the crews especially as we are already supplying marine versions of our solar panels to a number of boatyards in Europe and Asia. He particularly recommended that we contact Sven Hadrada of SailYard boats as they are apparently considering entering the race.
We’ve both worked with SailYard on several occasions. Do you think you could contact them as soon as possible and set up a meeting to explore ways of working together on this You could arrange to supply our solar panels free of charge in exchange for appropriate publicity space onboard and in the press.
Best regards
Anna

Which type of craft can enter the Solar Trophy

A. Ocean liners
B. Inflatable boats
C. Sailboats
D. Solar-powered yachts
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