Terms and conditions of use

About the service

Mendeleev is a free educational platform for learning the periodic table and chemistry. Using the periodic table, the element information and the atomic model does not need an account.

Creating an account is only needed for unlimited use of the AI assistant, saving your chat history and writing reviews.

Account

• Sign-up is done with an Iranian mobile number and verified with an SMS code.
• Each mobile number can have only one account.
• The username must be unique and reserved names cannot be chosen.
• The user is responsible for keeping their own password safe.
• At most five devices can be signed in to one account at the same time. To sign in on a sixth device, one of the earlier devices must be signed out.
• Changing the password automatically signs out all other devices.

Data and privacy

The information we store and how we protect it:

• Mobile number: is stored encrypted in the database and is not readable under normal conditions.
• Password: is never stored in plain form; only its encrypted hash is kept.
• AI chats: The text of messages is stored encrypted so that you can see your history.
• Devices: The browser name, operating system and network address are recorded to manage sign-ins.

Your data is not sold or handed over to any third party or service. Messages you send to the AI assistant are sent to the model provider to get an answer.

Using the AI

• The AI assistant only answers questions in the field of chemistry.
• Guest users get two free messages; they must sign up to continue.
• Each chat has a set limit, and once it is reached a new chat must be started.
• AI answers may contain mistakes and are not a substitute for a reliable scientific source.
• Abuse, mass posting or attempting to disrupt the service will lead to the account being restricted.

User reviews

• Writing a review is only possible for users with an account.
• Your review is shown together with your username.
• Offensive, promotional or unrelated reviews are removed.
• Each user can edit or delete their own review.

Limitation of liability

This service is an educational project and is offered without a guarantee of permanent availability. Its scientific content has been gathered carefully but may contain mistakes; for academic and research use, always check it against reliable sources.

These terms may change in the future, and changes will be announced on this same page.