Which statement is true about this reaction? Superscript 14 subscript 7 upper N plus superscript 1 subscript 1 upper H right arrow superscript 15 subscript 8 upper O. It is a practical source of energy on Earth. It occurs only outside the solar system. Its product is heavier than each of its reactants. It shows the critical mass of an element.

In a heat engine of 1000 j of heat enters the system and the piston does 500 j of work what is the final internal energy of the system if the inital energy was 2000 j we have to do all of these down here 1)write the equation 2)list out your know variables 3)plug the numbers into the equations 4)solve 5)write your solution statemtn that includes inital energuy and final energuy added

Given the following at 25c calculate delta hf for hcn (g) at 25c. 2nh3 (g) +3o2 (g) + 2ch4 (g) > 2hcn (g) + 6h2o (g) delta h rxn= -870.8 kj. delta hf=-80.3 kj/mol for nh3 (g), -74.6 kj/mol for ch4, and -241.8 kj/mol for h2o (g)

On the periodic table, elements are arranged by which of the following. a. mass numbers. b. increasing atomic number. c. alphabetical order. or d. density