1. Put a label above the pH values (e.g., "pH"), but resist the urge to put
a label above the date/time values. Select the two columns of data, from the
label row to the last row of the data. This is your data range. You can
select the entire range; if you select a single cell within the range, Excel
tries to find the range to plot (and it usually does pretty well).

2. You need an XY chart, not a Line chart. A line chart's date-scale axis
(incorrectly called a time-scale axis) only recognizes integer values, that
is, dates and not times.

- Jon
-------
Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
Peltier Technical Services, Inc. - http://PeltierTech.com
_______


"erik" wrote in message
...
Trying to plot data from two colums:
X-Axis: Column 1 is Date/Time (mm/dd/yy hh:mm, e.g. 11/21/06 13:10),
Y-Axis: Column 2 is pH (number to 2 decimal places, e.g. 8.24).

QUESTIONS:
1 - I do not know what DATA RANGE is and not sure what I should be
highlighting/selecting for data range.

2 - Can not get Date/Time data in column 1 to show properly on X axis of
chart...will show date but not time so all points are lumped into one area
on
top of each other...number format for chart and data have been changed to
be
the same.