(1.)I2(g)+H2(g)⇌2HI(g)△H=﹣9.48kJ/mol
(2.)I2(S)+H2(g)⇌2HI(g)△H=+26.48kJ/mol
下列判断正确的是( )
A:254 g I2(g)中通入2 g H2(g),反应放热9.48 kJ
B:1 mol固态碘与1 mol气态碘所含的能量相差17.00 kJ
C:反应(1)的产物比反应(2)的产物稳定
D:反应(2)的反应物总能量比反应(1)的反应物总能量低
若多项式 (x+1)(x−3) = x2+ax+b ,则a,b的值分别是( )
①理想不等于现实,理想高于现实 ②现实孕育着理想,是理想的基础
③理想来源于现实,是现实的升华 ④只要努力就一定能成功
根据短文,选择正确选项。
One day, the teacher asks the boys and girls a question. “Swallows(燕子) fly to the south before winter1,”he says. “But why don't cats and dogs do2?” Fox lifts (举) his3as usual. “Yes, Fox?” says the teacher4. Fox stands (站) up and says, “5they have no wings (翅膀).”