This is the critical caveat. If you search Google or Reddit for a direct download link to a free PDF (e.g., from Library Genesis or Z-Library), you are engaging in copyright infringement. Cengage Learning (the publisher) holds the rights to the 10th and 11th (upcoming) editions.
Searching for Douglas A. Skoog's (often titled Fundamentals of Analytical Chemistry ) yields several editions and related resources available in PDF format across academic and document-sharing platforms. Available Textbook Versions (PDF) skoog analytical chemistry pdf
Understanding mean, standard deviation, and confidence intervals. This is the critical caveat