$A$ reversible reaction is in equilibrium. If a factor is changed which affects it,then:

The reaction $C_2H_{6(g)} \rightleftharpoons C_2H_{4(g)} + H_{2(g)}$ is at equilibrium in a closed vessel at $1000 \ K$. The enthalpy change $(\Delta H)$ for the reaction is $137.0 \ kJ \ mol^{-1}$. Which one of the following actions would shift the equilibrium to the right?

At $25\,^oC$,the equilibrium $SO_2Cl_2(g) \rightleftharpoons SO_2(g) + Cl_2(g)$ is established in a closed vessel. When $Cl_2$ is added to the equilibrium mixture,which of the following statements is/are correct for the system?
$(1)$ Change in concentrations of $SO_2$,$Cl_2$,and $SO_2Cl_2$.
$(2)$ More $Cl_2$ is produced.
$(3)$ The concentration of $SO_2$ decreases and the concentration of $SO_2Cl_2$ increases.

In which of the following reactions are high temperature and high pressure favorable for obtaining a higher yield of products?

The yield of the products in the reaction,$A_{2(g)} + 2B_{(g)} \rightleftharpoons C_{(g)} + Q \ kJ$ would be higher at

Observe the following equilibrium:
$Fe^{3+}_{(aq)} + SCN^{-}_{(aq)} \rightleftharpoons [Fe(SCN)]^{2+}_{(aq)}$
(yellow) (colorless) (deep red)
Addition of aqueous oxalic acid solution to the above equilibrium: