The percent yield of this reaction is calculated as follows
Mg3N2 + 3H2O =2NH3 + 3Mgo
calculate the theoretical yield,
moles=mass/molar mass
moles Mg3N2= 3.82 g/100g/mol= 0.0382 moles(limiting regent)
moles of H2o= 7.73g/18g/mol = 0.429 moles ( in excess_)
by use of mole ratio between Mg3N2 to MgO which is 1:3 the moles of MgO = 0.0382 x3 = 0.1146 moles
mass =moles x molar mass
the theoretical mass is therefore = 0.1146mole x 40 g/mol = 4.58 grams
The % yield = actual mass/theoretical mass x1000
= 3.60/4.584 x100= 78.5%
<span>The mass number of an ion is calculated by adding the neutrons and electrons together. In this case 159+107=266. However, since this ion has a +1 charge, you must add 1 to the electrons. This would give a total mass of 267.</span>
Evaporation happens<span> when atoms or </span>molecules<span> escape from the liquid and turn into a vapor. Not all of the </span>molecules in a liquid have the same energy. <span>Sometimes a </span>liquid<span> can be sitting in one place (maybe a puddle) and its molecules will become a </span>gas<span>. That's the process called </span>evaporation<span>. It can happen when liquids are cold or when they are warm. It happens more often with warmer liquids. You probably remember that when matter has a higher temperature, the molecules have a higher </span>energy<span>. When the energy in specific molecules reaches a certain level, they can have a </span>phase change<span>. Evaporation is all about the energy in individual molecules, not about the average energy of a system. The average energy can be low and the evaporation still continues. </span>
