Consider the curves for specific impulse, chamber temperature, and molecular weight in Fig. $5-1.$ For Parts c & d$,$ you might review Fig. $3-2$ and Eq$.(3-16)$ in considering the questions.

a$.$ What is the value of the peak mixture ratio for shifting equilibrium of $RP-\frac{1}{L}Ox?$ Mark your point on Fig. $5-1$ on the back of this sheet.

b$.$ Is this point fuel rich $($excess fuel$)$ or lean $($excess oxygen$)?($Consider your answer in $1$ b above.$)$

c$.$ Why does the specific impulse drop from this peak value as the mixture ratio is reduced?

d$.$ Why does the specific impulse drop from the peak value when the mixture ratio is increased?

FIGURE $5-1.$ Calculated performance analysis of liquid oxygen and hydrocarbon fuel as a function of mixture ratio.