Chapter 1: Introduction to the Chemistry of Life

For the conversion of reactant A to product B, the change in enthalpy is $\mathbf{7}\mathit{k}\mathit{J}\mathit{m}\mathit{o}{\mathit{l}}^{\mathbf{-}\mathbf{1}}$and the change is entropy is$\mathbf{20}\mathit{J}{\mathit{K}}^{\mathbf{-}\mathbf{1}}\mathit{m}\mathit{o}{\mathit{l}}^{\mathbf{-}\mathbf{1}}$ . Above what temperature does the reaction become spontaneous?

Explain how organisms avoid reaching equilibrium while maintaining a nonequilibrium steady state.

The equilibrium constant for the reaction $\mathit{Q}\mathbf{\to }\mathit{R}$is 25.

1. If $\mathbf{50}\mathit{\mu }\mathit{M}$of Q is mixed with $\mathbf{50}\mathit{\mu }\mathit{M}$of R, which way will the reaction proceed to generate more Q or more R?
2. Calculate the equilibrium concentrations of Q and R.

At $\mathbf{10}\mathbf{°}\mathit{C}\mathbf{,}{\mathit{K}}_{\mathbf{e}\mathbf{q}}$for a reaction is 100 . At $\mathbf{30}\mathbf{°}\mathit{C}\mathbf{,}{\mathit{K}}_{\mathbf{e}\mathbf{q}}\mathbf{=}\mathbf{10}$Does enthalpy increase or decrease during the reaction?

Two biochemical reactions have the same ${\mathit{K}}_{\mathbf{e}\mathbf{q}}\mathbf{=}\mathbf{5}\mathbf{\times }{\mathbf{10}}^{\mathbf{8}}$at tem-perature ${\mathit{T}}_{\mathbf{1}}\mathbf{=}\mathbf{298}\mathit{K}$. However, Reaction 1 has $\mathit{\Delta }\mathit{H}\mathbf{°}\mathbf{=}\mathbf{-}\mathbf{28}\mathit{k}\mathit{J}\mathit{m}\mathit{o}{\mathit{l}}^{\mathbf{-}\mathbf{1}}$and Reaction 2 has.$\mathit{\Delta }\mathit{H}\mathbf{°}\mathbf{=}\mathbf{+}\mathbf{28}\mathit{k}\mathit{J}\mathit{m}\mathit{o}{\mathit{l}}^{\mathbf{-}\mathbf{1}}$The two reactions utilize the same reactants. Your lab partner has proposed that you can get more of the reactants to proceed via Reaction 2 rather than Reaction 1 by lowering the temperature of the reaction. Will this strategy work? Why or why not? How much would the temperature have to be raised or lowered in order to change the value of $\frac{{\mathbf{K}}_{\mathbf{2}}}{{\mathbf{K}}_{\mathbf{1}}}$from 1 to 10?

Identify the circled functional groups and linkages in the compound below

Practice drawing a simple condensation and hydrolysis reaction

The bacterium Thiomargarita namibiensis—at about 0.1 to 0.3 mm in diameter—is visible to the human eye. How does its size compare to the size of typical prokaryotic cells? How does it compare to the size of typical eukaryotic cells?

Explain why complementarity would have been necessary for the development of self-replicating molecules

Explain the selective advantages of compartmentation and metabolic pathways.