Format menu
Bond - fixed length and angle: If this menu item is checked, bonds will be drawn to specific lengths and angles.
Arrow - fixed length and angle: If this menu item is checked, arrows will be drawn to specific lengths and angles.
Set background color: This menu item allows you to change the background color of the drawing area.
Drawing settings... This item opens a dialog where you can set the lengths and angles of bonds and arrows and specify other format settings, such as double bond spacing.