1. How was matter and energy conserved in each demonstration? 2. What phase changes did you observe? 3. What kind/s of energy transfers did you notice in each scenario? 4. Identify an example of matter and energy conservation in the world around you.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

0.2348 grams of pbcl2 used to form 44.0 ml of solution.

If you burn 10 kilograms of wood in a fire (combustion) what is the weight of the products after the fire has finished burning the wood?