襄樊市很多家庭都用上了天然气，天然气的主要成分是_______，与煤 相比，使用天然气具有热值高、安全性好、污染少等优点

天然气的主要成分是甲烷，燃烧后的产物是水与二氧化碳，无污染且产热量较高是较清洁的能源，而含硫的煤燃烧会生成二氧化硫污染空气，二氧化硫与雨水结合会生成亚硫酸，从而形成酸雨．
故答案为：甲烷（CH ₄ ）；二氧化硫（SO ₂ ）．

“After Shenzhou seven” the man-carrying rocket lift-off, south central the elementary school organized to hold "“Shenzhou Seven” three after the sixth grade student Man-carrying rocket Lift-off" the view the feeling thesis competition.After the language section and the Young Pioneers battalion headquarters evaluation, selected: First award 8, second prize 14, third prize 7, and in the morning “wrote the expert” in October 14 to these to issue the certificate. On September 5, 2008, is makes the world China children's unforgettable great happiness day, also is our Chinese feels the arrogant time, because of our testimony “Shenzhou seven” a lift-off historical quarter.From September 25 to 28th, in these days, schoolmates all pays attention the television direct seeding, watches “the god attentively seven” the lift-off and the grand scene which roams through in the outer space, specially proud was spaceman Zhai Zhigang strolls for the first time in the outer space, he was wielding the Chinese national flag, beckoned to the world people.This indicated our Chinese in the science and technology a leap development, the Chinese may announce once again to the world person: “The Chinese is really good!”Many after very schoolmates watch have the experience deeply, writes own feelings, for example: Six (2) class of schoolmate Long Fei is writes like this: Saw this victory a quarter, I thought: “If I will later be able to become an outstanding scientist, I will certainly have to invent more advanced `Shenzhou rocket', not only will enable each person to be possible on the outer space, moreover will enable each person to come back safely.That, we now must grasp more knowledge, studies well, future will realize own ideal.” This has ideal schoolmate! This activity is carries on the patriotic education to schoolmates good source material, also stimulated them to have to deeply love the science, to learn the science since childhood, future will make the contribution with the scientific knowledge for the motherland!

Xiangfan ,the second city of Hubei province,lies
on the borders of the Han river.It has a roughly
population of 5,820,000.It has 3
districts,includingXiangyang District ,Xiangcheng
District ,Fancheng District ,and 3 county-level
cities and 3 counties.
Xiangfan is a famous national-level historical and
cultural city in China,with a history of over 2800
years.It was the location of major battles during
the Three Kingdoms period in 191 A.D.between Sun
Jian and Liu Biao and in 1267-1273 A.D.between the
Southern Song and the Mongols.Its major scenic spots
and cultural sites include Xiangyang City Moat,the
Pseudo-classic Street,Ancient Longzhong,Memorial
Temple to Mi Fu,Lu- men Temple.
Xiangfan is rich in water energy resource.Mineral
deposits include rutile,ilmenite,phosphorus,
barite,coal,iron,aluminum,gold,manganese,
nitre,and rock salt.Rutile and ilmenite reserves
rank high in China.Textile industry is the
mainstay.Machinery,chemical,electronics,and
construction material making are also Xiangfan's
industries.Xiangfan is rich in agricultural
resources,the chief farm products of Xiangfan
include grain,cotton,vegetable oil crops,tobacco,
tea,and fruit.Xiangfan is a well known automobile
hub (Dong Feng Motors ).In addition,there are
quite a few chemical fibre enterprises in the city (
Birla Jingwei Fibres from Aditya Birla Group).
Rail and highway transportation facilities in
Xiangfan are very good.Air routes from Xiangfan
Airport link Xiangfan with some other major cities
throughout China,such as Beijing,Shanghai,
Guangzhou and so on.

解题思路：天然气的主要成分是甲烷，含硫的煤燃烧时会生成一种主要的大气污染物二氧化硫，往往导致酸雨的产生．

天然气的主要成分是甲烷，燃烧后的产物是水与二氧化碳，无污染且产热量较高是较清洁的能源，而含硫的煤燃烧会生成二氧化硫污染空气，二氧化硫与雨水结合会生成亚硫酸，从而形成酸雨．
故答案为：甲烷（CH₄）；二氧化硫（SO₂）．

点评：
本题考点： 常用燃料的使用与其对环境的影响；防治空气污染的措施；化石燃料及其综合利用．

考点点评： 本题考查能源有关的知识，学习了含硫煤的燃烧时生成物二氧化硫的性质，有助于提高同学们的环保意识．