实验室需要 0.1mol/L的 H2SO4溶液980mL,欲用 98%、密度为1.84g/cm3的浓硫酸配制. (1)所需的主要仪器除量筒、烧杯、玻璃棒外,还需要
(4分)将1 mol I2(g)和2 mol H2置于2L密闭容器中,在一定温度下发生反应: I2(g) + H2(g) 2HI(g);△H<0,并达平衡。HI的体积分数w(HI)随时间变化如图曲线(Ⅱ)
Lin Qiao is a student of Grade Eight. She always works hard 31 her lessons, such as Geography, History, Computer Studies. English is her favourite 32 . She thinks that English is as
Prices of daily goods _____ through a computer can be lower than store prices. A. are bought B. bought C. been bought D.buying
14.下列句子中,没.有.语病的一句是 (3 分) A.此次会议发言要求每人五分钟,可轮到王老师,他足足讲了十分钟,罗列了六点建议, 还意犹未尽,
“今日幸颐和,明日幸北海,何日再幸古长安?……五十割交趾,六十割台湾,七十更割辽东地……”这是革命家章炳麟先生讽刺慈禧太后的脍炙人口
太阳表面温度约为6000K,主要发出可见光,人体温度约为310K,主要发出红外线,宇宙间的温度约为3K,所发出的辐射称为“3K背景辐射”。若要进行“3K
如图,在直三棱柱中, AB=1,,∠ABC=60. (Ⅰ)证明:; (Ⅱ)求二面角A——B的大小。