The queen is the most powerful piece on the board, when you deliberately allow your queen to be captured that is a sacrifice. The reasons for a queen sacrifice can vary, but generally, it is made to achieve one or more of the following objectives: 1.Immediate Checkmate 2.Decisive Material Gain 3.Positional Advantage 4.Tactical Advantage ..etc
En passant is a special pawn capture move in chess. It occurs when a pawn moves two squares forward from its starting position and lands beside an opponent's pawn. The opponent can capture the first pawn as if it had only moved one square forward. This move must be made immediately after the initial two-square advance, or the opportunity is lost.
