Hello. Today we started class by going over notes. First we learned about systems and surroundings. There are three systems: open, closed, and isolated. An open system can exchange both matter and energy with the surroundings. A closed system can exchange only energy with the surroundings. An isolated system can exchange neither energy nor matter with its surroundings.
Next we learned about exothermic and endothermic processes. They both can be chemical reactions or physical changes.
An exothermic process loses eneregy. The energy flows out of the system and to the surroundings. Exothermic processes have a negative q.
An endothermic process gains energy. The energy flows into the system from the surroundings. Endothermic processes have a positive q.
Remember: The q of a system is equal and opposite to the surroundings.
Then we did a short lab.
We had to fill a beaker with about 25g of ice and obtain a beaker with about 100mL of warm water. We recorded the initial temperature of the water. Then we mixed the ice with the water and waited for the ice to melt. Once it had melted we recorded the final temperature of the water. We then used the data we had to find the molar heat of fusion of ice.
In order to find the molar heat of fusion of ice, you have to find the q of the water. Next convert the grams of ice into moles. Then make a ratio (J/mol)
The next scribe is Danielle
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