A0.25 g sample of a pretzel is burned. the heat it gives off is used to heat 50. g of water from 18 °c to 42 °c. what is the energy value of the pretzel, in kcal/g?

What happened to the amount of carbon dioxide in the atmosphere from 2010–2017?

What is conserved in the reaction shown below? h2(g) + cl2 (g) --> 2hcl(g)a. mass onlyb. mass and moles onlyc. mass, moles, and molecules onlyd. mass, moles, molecules, and volume

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