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Pencil Tool

This is the default drawing tool; it is used to draw or change atoms and bonds.

Point the pencil cursor and click once to draw a C atom. Carbon is the default Current Atom value. Click, hold, and drag the mouse to the point you want another C node to appear and release the mouse; a second atom is drawn connected to the first by a single bond (the default Current Bond Value).

Modify an existing atom or bond by selecting a new value and then pointing to the atom or bond and clicking. For example, click on the O and then on the double bond in the Horizontal Tool Palette at the bottom of the drawing screen. Point to an existing C and click to modify it to an O and then point to an existing single bond and click to modify it to a double bond.

Notice that the pencil cursor changes to display an "A" or "--" when pointing to an atom or bond.

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