(A)2. When burned as a fuel, hydrogen(氢气) is a green energy source. A. considered B. concluded C. completed D. compared 相关知识点: 试题来源: 解析 答案见上2.A 【解析】句意:当作为燃料燃烧时,氢气被 认为是一种绿色能源。 consider意为“认为”, 此处是它的被动语态。 反馈 收藏 ...
M: Ok. Like all stars the sun is basically a giant nuclear reactor that burns hydrogen to create energy. But like any reactor, the sun needs fuel to keep going. It's been going strong for around 4. 5 billion years, and will probably keep burning for about five billion more. ...
A wave of developers have announced their intention to extract hydrogen from naturally occurring stores of the gas underground. But while this so-called gold or white H2is expected to be extremely cheap to produce, it is unknown exactly how it will compare to other methods of generating the mo...
How many grams of CO_2 is produced from 855 grams of C_6H_{12}O_6 in the process of cell respiration? Hydrocarbons, compounds containing only carbon and hydrogen, are important in fuels. The heat of combustion of cyclohexane, C6H12, is 936...
To answer the question about the type of chemical reaction that occurs when chlorine is involved in bleaching, we can break it down into several steps:1. Understanding the Reaction: When chlorine is used for bleaching, it typic
According to the equation below, what is the enthalpy change when 400.0 grams of propane is burned in excess oxygen? C3H8(g) + 5O2(g) arrow 3CO2(g) + 4H2O(l); Delta H = -2221 kJ If 10.50 moles of water react completely, according to the following equation...
The enthalpy change for the reaction of hydrogen gas with fluorine gas to produce hydrogen fluoride is -542 kJ for the equation as written: What is the enthalpy change per mole of hydrogen fluoride produced? The enthalpy change for the reaction below at 2...
This is particularly the case when plastics containing halogen - above all PVC - burn. If a fire breaks out, hydrogen halides are released from the plastic. Halogens combine with water, such as fire fighting water, but also with the moisture in the mucous membranes, to form acids, chlorine...
ASA tablets contain the analgesic acetylsalicylic acid, HC9H7O4, which has an acid hydrogen ion. During titration of a tablet of 0.250 g of ASA, 38.5 mL of KOH at 0.0223 M were required to reach end point. What was the percentage by mass of ...
In U.S. Pat. No. 4,139,501, Rudner, Noone and Pauly disclose flexible polyurethane foams having reduced tendency to form burning embers when ignited and burned, produced by incorporating into the foam-forming reaction mixture a melamine derivative wherein one or more hydrogen atoms have been...