A very poisonous diatomic gas used in world war II, is an early example of chemical warfare. At standard temperature and pressure a sample of this gas occupies a volume of 11.3 dm' and
weighs 35.5g. Calculate the molar mass of this gas. Identify the gas. (Round off your answers to
2 decimal places)

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.