Is gasoline burning a chemical change?GasolineGasoline is a homogeneous liquid consisting of organic compounds obtained from the distillation of petroleum and sometimes, ethanol and other additives. It is used as fuel in vehicles. The United States uses just over 40% of the total gasoline used ...
A. In the case of B. In case C. In case of D. In event of 相关知识点: 试题来源: 解析 A in case of sth.:假使,如果;in case:以防,万一;in event of:如果,以防;三项都不符合题意。in the cause of意为“在,,过程中”。句意:在化学变化中一种新物质生成了。反馈...
A. Wax turns into water B. Wax combines with oxygen to form carbon dioxide and water C. Wax turns into hydrogen gas D. Wax turns into oxygen gas 相关知识点: 试题来源: 解析 B。解析:蜡烛燃烧时,蜡与氧气发生化学反应,生成二氧化碳和水,这是蜡烛燃烧这个化学变化的本质。选项A蜡不会单纯地变成水...
请教一句关于as a result of which的从句原句:We may define chemistry as the science in which we deal with the chemical change in matter as a result of which it is possible to form a new substance.句子的意思我能明白:我们可以
The U. S. -China trade relationship has dominated headlines in recent months, but it's the illicit drug trade that some lawmakers and experts believe should be moved to the top of the list of issues between the two countries. Last year, more than 49,000
Recently,Rambouillet,a small historic French town,has teamed up with a company called Glowee to turn the city into a full-scale bioluminescence laboratory.The goal is to change the way in which cities use light.The company uses marine (海的) bacteria harvested from the coast o...
A. a chemical change is always faster. B. a physical change does not change the appearance of a substance. C. a chemical change produces new substances. D. a physical change always requires heat. 相关知识点: 试题来源: 解析 C。解析:化学变化和物理变化的区别是化学变化产生新物质。A 不一定...
A chemical change is different from a physical change because in a chemical change ___. A. the appearance changes B. the composition changes C. the size changes D. the weight changes 相关知识点: 试题来源: 解析 B。化学变化与物理变化不同在于化学变化中物质的组成发生了变化。反馈 ...
There is a good reason for this-mammals have the ability to keep their body at a constant temperature whatever the weather.They are “warm-blooded”. Mammals achieve this by chemically “burning” their food as fuel inside their bodies.This is kept under tight control by a region of the br...
It shows that the short but intense (剧烈的) exercise made the brain produce more of a chemical called “brain-derived neurotrophic factor (脑源性神经营养因子). People can remember things quickly with this chemical. 5 That’s the time when you need to sit down and start to remember ...