Conditional column K if 24 hours after column J

[Nanaia]

In column J I enter date and time [x/xx/xx x:xx] for approval emails being sent out. In column K I enter date and time of when approval for the sent email has been received. I am trying to figure out what the formula would be to conditional format column K to highlight a cell red if it has been after 24 hours of the date and time entered in the same row in column J. I also want the red highlighting to disappear once data has been entered into column K. If this is not possible I am more than happy to create another column. This is for my personal use so I just need it to flag so I can see what emails must have reminders sent out. Can anyone help?

 

[JamesCanale]

=AND(K2="",NOW()-J2>1)

 

[Nanaia]

=AND(K2="",NOW()-J2>1)

Thank you. This formula highlights the cell if a cell in column J has any value in it, whether the time+date is over 24 hours or only minutes old. It does not highlight the cell if there is a value in column K though.

 

[Nanaia]

You provided an excellent start. I already had a cell that displays the "current date+time" and I just replaced the [NOW()] within your formula and it worked! The ending formula was [=AND(K2=" ",$A$1-J2>1)]