An ideal gaseous reaction (which is a hypothetical gaseous reaction that conforms to the laws governing gas behavior) occurs at a constant pressure of 45.0 atm and releases 68.0 kj of heat. before the reaction, the volume of the system was 6.40 l . after the reaction, the volume of the system was 2.80 l . calculate the total internal energy change, δe, in kilojoules.

Achemist wants to extract copper metal from copper chloride solution. the chemist places 0.50 grams of aluminum foil in a solution containing 0.75 grams of copper (ii) chloride. a single replacement reaction takes place. (ii) chloride. a single replacement reaction takes place. which statement explains the maximum amount of copper that the chemist can extract using this reaction? a) approximately 0.36 grams, because copper (ii) chloride acts as a limiting reactant b) approximately 1.8 grams, because copper (ii) chloride acts as a limiting reactant c) approximately 0.36 grams, because aluminum acts as a limiting reactant d) approximately 1.8 grams, because aluminum acts as a limiting reactant

Which of these statements best explains why space exploration should be encouraged? it prepares humans to live without oxygen. it dispel myths about objects in space. it prevents comets and asteroids from striking earth. it creates technology to absorb harmful radiations in space.

If an atom has 12 protons and 13 neutrons