Identify a substance that is not in its standard state. refer to table b in appendix ii of the textbook to answer this question. identify a substance that is not in its standard state. refer to table b in appendix ii of the textbook to answer this question. ni(s) h2(g) o2(g) ba(s) co(s)

The phase of an element or a pure substance under standard conditions of temperature and pressure, 1 atm and is referred to as the standard state of that substance, at which the element will be stable.

Metals like Na, Li, K, Mg, Ca, Ni, Cu, Fe are all solids at standard conditions.

Bromine and mercury are liquids in their standard state.

Diatomic hydrogen, nitrogen, oxygen, chlorine, fluorine, and all noble gases are gases in their standard state.

Therefore, all the options are in the standard state except CO(s), carbon monoxide is a gas at room temperature.

answer: the value of enthalpy change will be -152.80 kj.

solution:

pressure = 1atm , temperature = = 298 k

given that pressure and temperature are same in both gases , the number of moles of both gases can be determined by the ideal gas equation.

according to reaction 3 moles no are reacting with 1 mol of ,then 0.49 mol of no will react with moles of ozone that is 0.16 moles of ozone. since, no is limiting reagent and is an excessive reagent.

enthalpy change for the reaction between the given volumes of the gases is :