Equilibria chemistry
 

The Equilibrium Law

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Self assessment

Question 1 of 5

K c for the equilibrium H2(g) + Cl2(g)  2HCl(g) is 1017. This means the following.

A

The reaction is very fast.

B

Hydrogen and chlorine hardly react.

C

There are 17 times more moles of HCl than Cl2 at equilibrium.

D

The reaction between H2(g) and Cl2(g) is nearly complete.

Which of the following represent a heterogeneous equilibium?

A

2H2(g) + O2(g)  2H2O(g)

B

H2O(l)  H+(aq) + OH–(aq)

C

NH4Cl(s)  NH3(g) + HCl(g)

D

NH4Cl(s)  NH3(g) + HCl(g)

What is the correct expression of Kc for the equilibrium:

PCl5(g)  PCl3(g) + Cl2(g)?

A

Expression for Kc is  \inline \dpi{100} K_{\textup{c}}= \frac{[\textup{PCl}_{5}]}{[\textup{PCl}_{3}]+[\textup{Cl}_{2}]}

B

Expression for Kc is  \inline \dpi{100} K_{\textup{c}}= \frac{[\textup{PCl}_{5}]}{[\textup{PCl}_{3}][\textup{Cl}_{2}]}

C

Expression for Kc is  \inline \dpi{100} K_{_{\textup{c}}}= \frac{[\textup{PCl}_{3}]+[\textup{Cl}_{2}]}{[\textup{PCl}_{5}]}

D

Expression for Kc is \inline \dpi{100} K_{\textup{c}}= \frac{[\textup{PCl}_{_{3}}][\textup{Cl}_{2}]}{[\textup{PCl}_{5}]}

What are the units of Kc if \inline \dpi{100} K_{\textup{c}}= \frac{[\textup{SO}_{3}]^{2}}{[\textup{SO}_{2}]^{2}[\textup{O}_{2}]}?

A

mol dm–3

B

mol–1 dm3

C

mol2 dm–6

D

mol5 dm–15

What is the equation of the equilibrium for which \inline \dpi{100} K_{\textup{c}}= \frac{[\textup{H}_{2}\textup{S}]^{2}}{[\textup{H}_{2}]^{2}[\textup{S}_{2}]}?

A

H2S(g)  H2(g) + S(g)

B

2H2(g) + S2(s)  2H2S(g)

C

2H2(g) + S2(g)  2H2S(g)

D

2H2S(g)  2H2(g) + S2(g)
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