1The chemist carefully measured the reagents into the flask and then sealed it for further analysis.
2Is it safe to use a plastic flask for storing highly corrosive substances, or should we opt for a glass one instead?
3The biologist gently swirled the flask to ensure the cells were evenly distributed before placing it in the incubator.
4When handling flammable liquids, always use a flask with a secure lid to prevent accidental spills or ignition.
5The archaeologist carefully excavated the ancient flask from the site, taking care not to damage its delicate ceramic structure.