I'm guessing these charts are embedded on the current worksheet rather than on separate tabs. If this is the case you can get all of the charts on a sheet by using the ChartObjects method on the worksheet object to return a collection. With this collection you can either loop through until you find the desired named Chart or you can skip straight to the desired one by specifying the known index number. Having got the ChartObject in question you just need to set the Visible property to True / False to hide and display. The following bit of code demonstrates the principle on the first Chart of Sheet1, amend sheet name / chart number as appropriate...
Code:
Sub Test()
Dim wb As Worksheet
Set wb = ThisWorkbook.Sheets("Sheet1")
wb.ChartObjects(1).Visible = False
MsgBox "Hidden"
wb.ChartObjects(1).Visible = True
MsgBox "Visible"
End Sub