The atomic symbol for an isotope with 4 protons and 5 neutrons is Beryllium ( Be)................
<span>One degree Celsius indicates the same temperature change as one </span>
Sr has an atomic number of 38 so we'll start there.
The closest noble gas is Kr with an atomic number of 36 so it'll look like this:
[Kr]5s^2.
Mass of the <span>solvent (H2O) in kg
D = m / V
1.02 = m / 125
m = 1.02 x 125
m = 127.5 g of H2O
127.5 / 1000 => 0.1275 kg
mass of solute in mg:
1000 x ( 1.86 x 10</span>⁻⁵ ) = 0.0186 mg
<span>
ppm = mass of solute in mg / mass of solvent in kg
ppm = 0.0186 / </span><span>0.1275
</span><span>
= 0.1458 ppm
hope this helps!
</span>
