I don't understand what input&output are in this phrase:chemical reactions that exist in energy input/output?
829949
energy input: reaction requires energy to take place - endothermic\nenergy output: reaction gives off energy when it takes place - exothermic
1022281
d)  both a and c\n\nbecasue in a chemical reaction   everythin on the product and teh reactant must be the same\n\nthe mass and atoms must be same
450334
Okay, cool!\nThe diagram is set up so that on the horizontal x-axis is the "reaction coordinate," which is basically just time as the reaction proceeds.  The vertical y-axis is energy.  \n\nThe potential energy of the reactants is where the graph curve starts, touching the y-axis.  The potential energy value is the y-value at this location.  \n\nWhere the graph curve levels off at the end is the products, so the potential energy of the products is the y-value where the curve levels off.  \n\nThe activation energy is how much energy had to be added into the system to get to the activated complex, located at the peak of the diagram's curve.  Take the y-value at the top of the curve and subtract from the the potential energy of the reactants.  \n\nThe heat of reaction is the difference in the potential energies of the products and reactants.  Take the potential energy of the products, and subtract from that the energy of the reactants.  \n\nIf a catalyst were added, the potential energy of the products and reactants remain unchanged, but the activation energy is less, so you draw a curve that starts in the same place and ends in the same place as the original diagram, but your curve just won't go up as high.  The hill for a catalyst is less steep.
395234
if you go from A to be and then B to A you should have no overall energy change. one will be an exothermic reacion and the other should be endothermic reaction
460906
DH reaction = DH products – DH reactants\n\nExample:  2A + B -- C\nDH = DH C – (2 DH A + DH B)\n\nIf DH is negative: exothermic reaction \nIf DH is positive: endothermic reaction
9127
In nuclear reactions, MASS is converted into energy.
446541
An acid and a base react to form a salt and water.  For example:  NaOH + HCl ==> NaCl + H20.  The products will always include some sort of salt, as well as water, and the reation will always be exothermic, meaning energy is released.
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U CAN MAKE A PROJ ON REACTIONS ON THE FOLLOWING PTS  .\n INTRO OF REACTIONS\nDEFINITION OF A REACTION\n TYPES OF REACTIONS\n THEN, DESCRIBE THEM SEPARATELY
316710
well energy is used only in the beginning to start the reaction. otherwise an exothermic reaction will give out tremendous amount of heat energy.
303776
Gasoline + Oxygen = CO2 + H2O + NOx + SO4 + energy
28195
Electricity is a form of energy.\n\nIt can be generated from other forms of energy, for example, chemical energy (burning fuel, or a battery), mechanical energy (a windmill), nuclear energy (atomic fission reaction like in a power plant).\n\nIn a battery electrical energy is converted from the  potential energy stored in chemicals which is released when they combine.\n\nIn a fuel cell, chemical energy is released in another type of chemical reaction.\n\nNuclear plants, windmills, hydroelectric dams or burning fuel in a generator turns a turbine or motor which moves a coil of wire through a magnetic field which produces energy.\n\nIn thermoelectric energy, heat is turned into electricity when two different metals are heated.
747557
A reaction tends to be spontaneous if  it causes an increase in the entropy of the system, and/or a decrease in the enthalpy of the system \n\nBoth reactions are endothermic (increase in enthalpy) becuase of positive delta H values.\nBoth have an increase in entropy (positive delta S value for the first one, production of a gas for the second)\n\nSo I'd say statements ll and lll are true.
511885
Energy can take the form of heat, light, vibration, momentum or sound. It can also be stored as potential energy. Anytime you interconvert among these forms of energy, you can say it is "transferred". Chemical reactions can include some or all of these, with chemical bonds representing stored potential energy.\n\nIn nuclear reactions, you can say that energy and matter are interconverted as well.
857176
S(s) + O2(g)------>SO2\n\n2Mg(s) + O2(g) -------> 2MgO(s)\n\nH2(g) + Br2 (g) -------> 2HBr(g)\n\n4Fe(s) + 3O2 -------> 2Fe2O3 (s)\n\nThen there are single replacement \n\nA + BC-------> AC + B\nZn(s) + 2HCl(aq)------->ZnCl2 (aq) + H2 (g)\nwhere one element replaces another\n\nthen there is double replacement \n\nAB+CD -------> AD + BC\n\nIn this one the positive ions in the reacting compounds switch places\n\nBaCl2 (aq) + Na2So4 (aq) --------.BaSo4 (s) + 2NaCl (aq)
799142
Hi Kitty,\nHere is what, I think, you need.\n\nExothermic, dH < 0, Entropy increases (dS > 0), Reaction is spontaneous and dG < 0\n\nExothermic, dH < 0, Entropy decreases (dS < 0), Reaction is spontaneous only at low temps, if |T dS| < |dH|\n\nEndothermic, dH > 0, Entropy increases (dS > 0), Reaction is spontaneous only  at high temps, if T dS > dH\n\nEndothermic, dH > 0, Entropy decreases (dS < 0), Reaction is not spontaneous, dG > 0
427297
1: will release carbon dioxide gas from carbonates\n\n2: will produce hydrogen when reacted with metals such as iron, zinc etc.
979402
reactant(s)\nSynthetic