Calculate the heat energy needed to heat 45.0 g of copper from 23.0°C to 30.0°C. Use chart above for specific heat of water. Use units and show all work.

For each of the following mixtures decide if filtering would be suitable to separate the substances. explain your answers. oil in water sugar in water sand in water chalk in water tea leaves in a cup of tea

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.

No copying 15 pts how does a free-body diagram tell you about the net force on an object?