2.303是哪来的15.已知反应:-|||-dfrac (1)(2)(H)_(2)(g)+dfrac (1)(2)(Cl)_(2)(g)leftharpoons HCl(g)-|||-在298.15K时的 _(1)^theta =4.9times (10)^16, _(m)(H)_(m)^theta (298.15K)=-92.31kJcdot (mol)^-1, 求在500K时的K2。

2.303是哪来的