The decrease in atomic size as you move from left to right across the periodic table becomes less pronounced as you move
the periodic table. *
O down
across
O diagonally
O horizontally

2b2t

explanation:

2b2t

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.