The actual formula for volume for a cube is the length multiplied by the width and then multiplied by the height. Since all three measurements are the same, the formula results in the measurement of one side cubed. For the example, 5^3 is 125 cm^3. Multiply the volume by the known density, which is the mass per volume.
I don't know terribly much about radioactive decay, but yes, it WILL decay. If it's half life is 25 days, it will be completely consumed in 50 days. By 100 days, it should be long gone. As far as I know, the reason for this is (besides the simple math which is self-explanatory) the Thorium has so many protons/neutrons, it's unstable and thus undergoes radioactive decay as it cannot maintain stable form.
I hope this helps! :)
In order for us to help we need more information. Possibly the amount of grams you used for Mg in trial 1 or something similar to this.
Intermolecular forces in solids are strongest than in liquids and gases. Gases have the least strong intermolecular forces. Intermolecular forces are weak and are significant over short distances between molecules (determined by Coulomb’s law). The farther away from the molecules the weaker the intermolecular forces. Since molecules in solids are the closest, the intermolecular force between them as the strongest. Conversely, since gas molecules are farthest apart, the intermolecular forces between them are the weakest.
An A horizon is a mineral horizon, It forms at the surface as topsoil. O horizon turns eventually into topsoil