The atomic mass of Europium is 152 amu
Work:
151(0.4803) = 72.52 amu
153(0.5197) = 79.5 amu
72.5 + 79.5 = 152 amu
Answer:
Chemical change :has change in mass, heat is needed, new element is formed, hard to reverse.......
Physicalchange:does not have change in mass, heat is not necessary, no new element is formed, easy to reverse
The volume of H₂ evolved at NTP=0.336 L
<h3>Further explanation</h3>
Reaction
Decomposition of NH₃
2NH₃ ⇒ N₂ + 3H₂
conservation mass : mass reactants=mass product
0.28 NH₃= 0.25 N₂ + 0.03 H₂
2 g H₂ = 22.4 L
so for 0.03 g :
<span>UV gel enhancements rely on ingredients from the monomer liquid and polymer powder chemical family. The chemicals from the polymer powder family </span><span>can absorb and retain extremely large amounts of a liquid relative to their own mass. Water-absorbing polymers, </span>can absorb aqueous solutions through hydrogen bonding with water molecules.
Water would have a much lower boiling point much like its other hydrides and it would loss its ability to dissolve polar substances plus it couldn't form water columns so no more cohesion between water molecules
