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.
A keystroke is typing one character on a keyboard (not stroking your keyboard like a cat). Every time you hit a key, you perform a keystroke. Therefore, 5400 keystrokes in one hour means hitting 5400 keys in one hour, or 90 keys a minute (5400 Ã· 60 minutes). Sometimes keystrokes per hour (KSPH) or keystrokes per minute (KSPM) are used to measure typing speed instead of words per minute (WPM).