rmine: The concentration of at the equilibrium stage when being placed in a flask at  a pressure of 4.0 atm. Given Data: The equilibrium REACTION isInitial pressure of is 4.0 atm Kp, the equilibrium constant, depends on partial PRESSURES exerted by the gaseous components in the given reaction. Kp = 0.04 atm Formulas to be used: Law of chemical equilibrium: Kp is equal to the ratio of the product of  partial pressures of the PRODUCTS of the given reaction, each being raised to the power of their corresponding coefficients to the product of the partial pressures of the reactants, each being raised to the power of their corresponding coefficients. Calculation: Step 1: Diagnose the values to be assigned in the law of chemical equilibrium Initial concentration of = 4.0 atm Initial concentration of = 0 atm Initial concentration of = 0 atm Let the pressure of at equilibrium = p atm So, the pressure of at equilibrium = p atm The pressure of at equilibrium = 4.0-p atm Step 2: Substitute the values obtained in the law of chemical equilibrium Step 3: Using the FORMULA for quadratic equations, we get By taking the positive VALUE alone,  We get p =0.76/2 =0.38 Hence at equilibrium, the pressure of = 4-p-4-0.38 = 3.62 atm