Which type of container is best used for heating substances at high temperatures?

The best container for heating substances at high temperatures is a crucible. Crucibles are specifically designed to withstand extreme heat without breaking or degrading. They are typically made from materials like ceramic, porcelain, or certain metal alloys that can tolerate high temperatures, making them suitable for processes such as melting metals or conducting high-temperature chemical reactions.

In contrast, glass beakers, while they can be used in heating applications, are generally not designed for very high temperatures and may shatter or crack if exposed to rapid temperature changes or excessive heat. Plastic containers are inappropriate for high-temperature heating, as they can melt or release harmful chemicals when exposed to intense heat. Petri dishes are used primarily for microbial cultures and are not intended for heating; they typically cannot endure high temperatures and can warp or melt.

Therefore, crucibles are the ideal choice for safely handling and heating substances at elevated temperatures.