A:一种催化剂只能催化一个化学反应
B:催化剂在化学反应前后质量和性质都不变
C:催化剂能加快化学反应速率,也能减慢化学反应速率
D:如果没有二氧化锰作催化剂,氯酸钾加热不会分解
在日常生活中,经常会提到笼统的“快”,下面关于“快”的叙述正确的是( )
在20世纪初出现的资产阶级革命组织中,孙中山领导的中国同盟会是第一个资产阶级政党,是因为
The Dress That Turns into a Coca Cola Machine This specially designed dress looks like a normal dress,but if you unfold it and cover yourself,you may look like a Coca Cola vending machine(自动售货机). Because there are many vending machines like that on the street,it must be easy for you to hide.If you feel that someone is following you or there is some danger,you can disappear within five seconds.But don't use it to scare your classmates.That'll be rude. The M-Dress is a nice black dress.It is also a mobile phone.It accepts a standard SIM card and allows the wearer to receive calls without carrying an actual(真实的) phone in their pocket or purse.You just need to bring your hand to your ear when you want to answer a phone call.When you finish talking and release your hand,the call will close.It is fashionable and useful.But it will certainly be an embarrassing moment when your dress rings in public. Air Conditioned Jackets You will love these air-cooled jackets in summer time when it is very hot outdoors.The jacket has fans that draw air in.The fan is powered by an inside battery.Now it is possible to spend nearly every second of your day with cool air.