A chemist reacted 57.50 grams of sodium metal with an excess amount of chlorines. The chemical reaction that occurred is shown.
Na + Cl -> Nac
Ir the percentage yield of the reaction is 86%, what is the actual yield?
Show your work, including the use of stoichiometric calculations and
conversion factors.

Write a paragraph that provides examples of each stage of volcanic activity, a description of the volcano, and facts about each stage.

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.

Describe at least two advantages and two disadvantages of using hydropower as a source of energy.