rx黑色提车作业

帮我回答以下的化学问题,要尽快,1、氧气的性质有：,.2、现有A、B、C、D四种物质.A是无色无味的气体.B在A中燃烧发出明亮的蓝紫色火焰,同时生成一种无色有刺激性气味的气体C.D是一种无色的 这道化学题怎么做?谢谢! 开发新能源,使用清洁燃料,可以达到提高能效、减少污染的目的.（1）由C、H、O三种元素中的两种和三种分别组成的燃料物质甲和乙,其分子中均有氧,且1个乙分子中含有18个电子,则甲和乙分别 求这道化学题的答案http://www.jyeoo.com/chemistry/ques/detail/ddf61ea3-6859-4204-94d1-9ba98b9f5f4d 这题怎么做?化学 我知道二氧化碳的总质量是35.2g+1.8g-25g+25g*3-82.6g=4.4g可就是不懂它的意思 这个题怎么做 化学高手来 特别是如何运用那些 什么离子啊 原子啊 电荷守恒?看了很多,但就是觉得晕especially计算题！什么氧化还原啊 金属啊 1/3+1/(1+2)*(3+2)+1/(1+4)*(3+4)+.1/(1+2008)*(3+2008) “京都协议书”是为减少二氧化碳而制定的国家公约某研究小组为监测空气中二氧化碳的含量,进行了如下实实验：用50mL注射器吸取红色含酚酞的稀氨水（氨水是一种碱,具有碱的性质）10mL, 救救我 某单位购买甲、乙两种钢笔共100枝,已知甲钢笔每支3元,乙钢笔每支2元,并且甲、乙两种钢笔所用的钱数一样多.购买甲、乙两种钢笔的支数比是多少?甲、乙两种钢笔各买了多少枝? 谁来救救我该这题目怎么做 5道题的说,谁来救救我 He became _______ and _______(fat) after he stopped exercising.Policemen make our city a____(save) place.This kind of yogurt cost more than 10 yuan in the supermarket.（more than 10 yuan划线）_____ _________ ______ this kind of yogurt cost in the 波斯湾地区的国家是怎样将沙漠变成宝地的? 第11题,快 explain why there is no color change when universal indicator paper is added to a solution of HCl in methylbenzene? magnesium and bromine react with each other to form a sustance X.(a) give the name of X Q.express as an ion1.FeCl22.CuO3.Fe2S34.CrCl3Q.Calculate each of the following quantities in 2.20 moles H3PO41.moles of H2.moles of O3.atoms of P4.atoms of OQ.Calculate the number of grams in each of the following1.1.50moles of Na2.3.05moles of Ca3.0 几道英语化学题!1.how are the atomic numbers and the atomic masses of the elements related to how the elements are arranged on the periodic table?2.how does the number of electrons relate to the arrangement what is the different in the number o Vitamin B12,cyanocobalamin,is essential for human nutrition.It is concentrated in animal tissue but not in higher plants.Although nutritional requirements for the vitamin are quite low,people who abstain completely from animal products may develop a members of the homologous series (CnH2n) are considered to have two different kinds of reactions.Explain why neither of them can take place in a poly(propene) mesh inserted in living body tissues to avoid reopening how is it possible to use carbon dating to determine the age of a fossil if the among of Carbon-14 has already decayed?How do you know what the initial amount of Carbon 14 was?Show the beta decay of a carbon 14atom.大意就是 怎么用炭14去确 在32°C时某一价金属硫酸盐饱和溶液溶质的质量分数为36.3%,取足量这种饱和溶液,蒸发掉50克水,再加入10g这种硫酸盐的无水盐,冷却到32°C,结晶析出这种盐的含10个结晶水的晶体314.36克.通过计算 1,化学方程式需要背的吗?要背到滚瓜烂熟的?2,那些物质a和物质b反应,然后生成物质c,这些也要背的很熟是吗?好比如 钠和氧气反应生成氧化钠,这些要背到很熟是吗?熟到一看到钠和氧气就会自 高中化学题,求大神,谢谢了,会给好评的 第六题…答案B…求大神讲明白 请大家帮我解答一下——————————————c200h200中最多有多少碳碳叁键?如果列式的话,（200*2+2-200）/4这个是怎么回事 铜锈高温灼烧条件下充分反应的产物是神马.是氧化亚铜还是氧化铜. 由NaOH、AlCl3、MgCl2三种固体组成的混合物溶于足量水中,有0.58 g白色难溶物析出,向所得溶液中逐滴加入0.5 mol·L-1的盐酸,加入盐酸的体积和生成沉淀的质量如图所示http://hiphotos.baidu.com/%E8%F3%B5%D9 将5.6gFe投入热的浓硝酸,产生红棕色气体A,把所得溶液减压蒸干,得到20gFe(NO3)2和Fe(NO3)3的混合物,将该固体在高温下加热,得到红棕色的Fe2O3和混合气体B,A、B气体混合通入足量水中,在标准状况下