An aluminum can of a soft drink is placed in a freezer. later, you find that the can is split open and its contents frozen. work was done on the can in splitting it open.

The number of grams of Kool-Aid® powder needed.

The ammonia/ammonium buffer system is used to optimize polymerase chain reactions (PCR) used in DNA studies. The equilibrium for this buffer can be written as NH4 + (aq) ? H + (aq) + NH3 (aq) Calculate the pH of a buffer that contains 0.

Which of the following laboratory procedures best illustrates the law of conservation of mass? Recording the rise in water level when a 25 g piece of wood is placed in 200 mL of water Synthesizing 36 g of H2O plus leftover reactants by combining 4 g

Which of the following reactions shows that the formation of NO2 requires 33.1 kJ/mol? O A. N (9) + 20 (9) ► NO2 (g) + 33.1 kJ O B. įN2 (g) + O2 (g) + 33.1 kJ → NO2 (9) O c. 1 N2 (9) + O2 (g) NO2 (g) + 33.1 kJ OD. N (g) + O (g) + 33.1 kJ → NO2 (9)

What must be done to be certain that a chemical change has taken place? a. Check for the production of bubbles before and after the change. b. Demonstrate that a release of energy occurred after the change. c.

Which statement correctly describes why a compound is a pure substance? O A compound is not a pure substance because each of its molecules is m elements A compound is a pure substance because its molecule cannot be broken O A compound is not a pure

What negative impact did chemistry have on society through the production and use of chlorofluorocarbons?

A food web shows the easiest way to get the most energy out of a producer the path a producer has to take to reach the top of the web how all organisms are connected through energy all of the possible energy pathways through an ecosystem

What phase change is endothermic

A Gran plot for a potentiometric titration resulted in a slope of 5.56 x 105. Measurements were made using SCE as the reference electrode and the analyte Eo was determined to be 0.354 V.