If a chemical reaction requires 250 J of energy to convert reactants to products,
how much energy is required to turn the
products back into the reactants?
What law is being used?

Nitric oxide (no) can be formed from nitrogen, hydrogen and oxygen in two steps. in the first step, nitrogen and hydrogen react to form ammonia: n2(g) + 2 h_2(g) rightarrow 2 nh_3 (g) delta h = -92. kj in the second step, ammonia and oxygen react to form nitric oxide and water: 4 nh_3(g) + 5 o_2(g) rightarrow 4no(g) + 6 h_2o(g) delta h = -905. kj calculate the net change in enthalpy for the formation of one mole of nitric oxide from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .

Each of the following compounds contains a metal that can exhibit more than one ionic charge. provide systematic names for each of these compounds. (a) cr(clo3)6 (b) mo(cn)6 (c) cr2(so3)3 (d) v(clo2)2 (e) v(cn)5 (f) os(clo2)4

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)