equilibrium expression and shift?

Question

What is the equilibrium expression for the following reaction: H2 (g) + I2 (g) 2 HI (g) ? a)[H2][I2]/[HI]2 b)[HI]2/[H2][I2]
c)[2 HI]/[H2][I2] d)[H2][I2]/[2 HI]

What change will maximize the production of H2 in the following reaction conducted in a sealed container? CH4 (g) + H2O (g) CO (g) + 3 H2 (g) a)removing water vapor b)increasing the volume c)decreasing the volume d)adding carbon monoxide

What is the equilibrium expression for the following reaction: SnO2 (s) + 2 CO (g) Sn (s) + 2 CO2 (g)? a)[CO]2/[CO2]2 b)[CO2]2/[CO]2 c)[SnO2][CO]2/[Sn][CO2]2 d)[Sn][CO2]2/[SnO2][CO]2

Which equilibrium will shift to the right at an increased pressure? a)2 H2O2 (l) 2 H2O (l) + O2 (g) b)PCl3 (g) + 3 NH3 (g) P(NH2)3 (g) + 3 HCl (g)
c)NaOH (aq) + HCl (aq) NaCl (aq) + H20
d)P4 (s) + 6 Cl2 (g) 4 PCl3 (l)

Answer 1

<1> it is b because when you write an equilibrium expression, the formulae is products/reactants. <2> is b when volume increases, the pressure decreases that the forward reation is favoured where there is greater amount of particles. <3>is b like what i said before but nSubstance becomes [substance]n as power and solids are excluded. <4> is d as increased pressure wants less amount of particles, 4 in right and 7 in left, so right reaction is wanted. Sorry if I can't explain.

Answer 2

b, b, b, d