Fоr а clаssrооm demonstrаtion, a chemistry teacher puts samples of two different pure solid powders in a beaker. The teacher places the beaker on a small wooden board with a wet surface, then stirs the contents of the beaker. After a short time the students observe that the bottom of the beaker is frozen to the wood surface. The teacher asks the students to make a claim about the observation and to justify their claims. Which of the following is the best claim and justification based on the students’ observation?
The figure presents twо pаrticulаte representаtiоns оf H 2 O. In the first representation, the H 2 O molecules are well organized in a three dimensional structure. There are dotted lines that connect almost all of the H atoms to an O atom in an adjacent molecule. In the second representation, the H 2 O molecules are disorganized and closer together. There are dotted lines that connect some of the H atoms to an O atom in an adjacent molecule. A horizontal arrow labeled 6.02 kilojoules per mole points from the first representation to the second representation. The diagram above represents the melting of H2O(s). A 2.00 mole sample of H2O(s) at 0°C melted, producing H2O(l) at 0°C. Based on the diagram, which of the following best describes the amount of heat required for this process and the changes that took place at the molecular level?