Chess/Optional homework/Solutions

This page gives the solutions to all the problems in the optional homework. Please try to solve the problems yourself before you look here. The solutions are given in algebraic chess notation.

Optional homework 1Edit

Problem 1Edit

This is a standard endgame position. White sacrifices his h-pawn in order to queen his g-pawn.

1. Kf4 Kg7
2. Kf5 Kh8

Any other move allows the h-pawn to queen.

3. Kg5

Or Ke5 or Ke6, but not Kf6?? stalemate.

3... Kg7
4. h8=Q+ Kxh8
5. Kf6! Kg8
6. g7 Kh7
7. Kf7 Kh6
8. g8=Q Kh5
9. Qg3 Kh6
10. Qh4 mate.

Problem 2Edit

1. Kb7!

White must not allow Black's king to reach c7 or c8 because White will not be able to queen the pawn. This is a special rule that applies only for a pawn on the edge of the board. Black's king will either stalemate White's king in the h8-corner, or it will block the pawn and be stalemated itself.

After the text move, White advances the pawn directly to h8 in 5 moves. There is nothing Black can do to stop this.

Optional homework 2Edit

Problem 1Edit

The Exchange Variation of the Ruy Lopez is defined by the following moves to open the game:

1. e4 e5
2. Nf3 Nc6
3. Bb5 a6
4. Bxc6 dxc6

Now if White plays

5. Nxe5?!

Black responds

5... Qd4!

Black's queen forks the e5-knight and the e4-pawn. White must defend or withdraw the knight and give up the pawn. Thus, Black achieves material equality with a slightly better position.

White's usual moves in the Exchange Variation are 5. O-O and 5. d4.

Problem 2Edit

This position can arise in the Exchange Variation of the Queen's Gambit Declined. The first moves are

1. d4 d5
2. c4 e6
3. Nc3 Nf6
4. Bg5 Nbd7
5. cxd5 exd5

Now if White plays

6. Nxd5??

Black responds

6... Nxd5!
7. Bxd8 Bb4+
8. Qd2 Bxd2+
9. Kxd2 Kxd8

Black exchanges queens and winds up a knight ahead. Even though Black's knight on f6 was pinned to the queen, it can still move, so in this particular variation, it protects the pawn on d5. This is a well-known trap, played by Daniel Harrwitz in the 1850s.

White usually plays 6. e3 or 6. Nf3 instead. These moves provide an escape from the bishop check on b4, so Black must protect the d5-pawn with 6...c6 or 6...Be7.

Optional homework 3Edit

Problem 1Edit

The game Z. Djordjevic vs. M. Kovacevic, 1984, began with the following moves:

1. d4 Nf6
2. Bg5

This is the Trompowski-Torre attack.

2... c6
3. e3??

This move cuts off the bishop from returning to d2. 3. Nf3 or 3. Bxf6 were called for, but almost any move (such as 3. c4) would have allowed White to save his bishop by withdrawing it to d2.

3... Qa5+

White resigned, as he loses his bishop to a queen fork while his king gets out of check.

This is the shortest serious tournament game in history, according to Tim Krabbé's chess records website.

Problem 2Edit

The game K. Shirazi vs. J. Peters, 1986 began with the following moves:

1. e4 c5
2. b4!?

This is the Sicilian Wing Gambit.

2... cxb4
3. a3 d5!
4. exd5 Qxd5
5. axb4??

White must play 5. Nf3 (or 5. Bb2) to prevent what happens next.

5... Qe5+

Black's queen forks the White king and rook. White must get his king out of check, then Black captures the rook on a1.

Last modified on 30 June 2009, at 20:40