To determine the amount of energy absorbed by a 2.30-gram ice cube melting completely, we use the heat of fusion of ice. The heat of fusion is the amount of energy required to change 1 gram of a substance from solid to liquid at its melting point.
Given:
- Mass of the ice cube ([tex]\( m \)[/tex]) = 2.30 grams
- Heat of fusion of ice ([tex]\( \Delta H_f \)[/tex]) = 334 joules/gram
We use the following formula to calculate the energy ([tex]\( Q \)[/tex]) absorbed:
[tex]\[ Q = m \times \Delta H_f \][/tex]
Substitute the given values into the formula:
[tex]\[ Q = 2.30 \, \text{grams} \times 334 \, \text{joules/gram} \][/tex]
Performing the multiplication:
[tex]\[ Q = 767.9999999999999 \, \text{joules} \][/tex]
Expressing the answer to three significant figures:
[tex]\[ Q \approx 768 \, \text{joules} \][/tex]
Thus, the amount of energy absorbed was [tex]\( 768 \)[/tex] joules.