Strontium-90 has a half-life of 28.8 years. What mass in grams of a 56.0 g sample will remain in the body after 115.2 years?

answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.

that tool would be a compass

5.6⋅10−^19  j

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