The standard enthalpy of formation. The enthalpy of formation is the energy change when 1 mole of a substance is formed from its constituent elements in their standard states.Particular points to note: 1  The elements are in their usual states under standard conditions. i.e at 25ÂºC and 1 atmosphere pressure (100 kPa).he standard enthalpy of formation. The enthalpy of formation is the energy change when 1 mole of a substance is formed from its constituent elements in their standard states.
Microsoft bumped the layout to 104 keys with the addition of Windows keys and a Menu key a bit later, but the layout is essentially the same. This is a rule-of-thumb, as no two keyboards are exactly the same. The number of keys on a full size keyboard varies, some having media keys, etc.
So the piano keyboard actually has only 12 different keys; 7 white keys and 5 black keys. The rest of the keys are just repeated with either higher or lower pitch. Here is a piano keyboard diagram with the note names of the white keys, or the basic notes: You can see that the 7 basic notes are repeated over and over. But each time the pitch (how high or low the tone is) is sounding one octave higher (if you go to the right).