Although the data is not stated, the standard enthalpy of formation of ammonia is -46 kJ/mol.
The standard enthalpy of formation of a substance is the change in enthalpy that occurs when one mole of that substance is produced from its elements in their standard states. The fact that the standard enthalpy of formation for ammonia is negative indicates that the formation of ammonia is an exothermic, or energy releasing, reaction.
We are given the amount of Nitrogen gas and hydrogen gas reacted to form ammonia:
N2 = 19.25 grams
H2 = 11.35 grams
Set-up a balanced chemical equation:
N2 + 3H2 ==> 2NH3
The theoretical amount of ammonia that will be produced from the given amounts is:
First, we need to determine the limiting reactant to serve as our basis for calculation.
number of moles / stoichiometric ratio
N2 = 19.25 g/ 28 g/mol / 1 = 0.6875
H2 = 11.35 g/ 2 g/mol /3 = 1.89
The limiting reactant is N2.
0.6875 moles N2 * (2 NH3/ 1 N2) * 17 g/mol NH3
The amount of NH3 produced is 23.375 grams of ammonia. <span />
the cell structure represented by x is the nucleus
Fresh water freezes faster
Answer:
If you want to separate black grapes from the mixture of black and green grapes, then you will simply pick black grapes using your hands from the mixture. In this way you are actually using handpicking separation method.
Explanation:
