Which fossil is the most effective?
fossil 1- 245-65 mya
fossil 2- 419-240 mya
fossil 3- 551-505 mya
fossil 4- 540-500 mya

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 .

Find the number of grams of hcl needed to react completely with .50 moles of magnesium.

What is the empirical formula of c6h18o3? ch3o c2h5o c2h6o c2h5o5