Another gas that was used to fill balloons was hydrogen. The reason why hydrogen is not used today is because it use to cause many fires when it was used to fill balloons up.
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Answer is: <span>concentration of fluoride in the water in parts-per-million is 1 ppm.
</span>Parts-per-million (10⁻⁶) is<span> present at one-millionth of a </span>gram per gram of sample solution, f<span>or example mg/kg.
</span>m(fluoride) = 500 g · 1000 mg/g = 500000 mg.
m(water) = d(water) · V(water).
m(water) = 1 kg/L · 500000 L.
m(water) = 500000 kg.
arts-per-million = 500000 mg ÷ 500000 kg = 1 mg/kg = 1 ppm.
I think it is the more fertile the soil
False; Because when 2 substances are mixed another substance is created.
If the solvent-solute interactions are weaker than the average of the solvent-solvent and solute-solute interactions, then heat is absorbed from the surroundings and the overall mixing process is said to be endothermic process.
The endothermic process can be defined as the process in which the reactants the will absorbed the heat from the surroundings . the heat is gained from the surrounding in the endothermic process and the surroundings temperature will decreases.
The solvent - solute interaction < solute - solvent interaction \and the solute solute interaction then the solution may be or may not be formed.
Thus, then heat is absorbed from the surroundings and the overall mixing process is called as endothermic process.
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