Answer:
9
Explanation:
atomic mass = number of protons + number of neutrons = 4+5 = 9 amu
Fe + heat ----> Fe_54 + + neutrons
Advantages
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Disadvantages
Solar panels can be expensive to install resulting in a time-lag of many years for savings on energy bills to match initial investments.Electricity generation depends entirely on a countries exposure to sunlight; this could be limited by a countries climate.Solar power stations do not match the power output of similar sized conventional power stations; they can also be very expensive to build.Solar power is used to charge batteries so that solar powered devices can be used at night. The batteries can often be large and heavy, taking up space and needing to be replaced from time to time.
Since the heat of solution of KI is 20.3 kJ/mol, the answer to the question is a. Exothermic, ΔH is positive
There are two types of chemical reactions namely exothermic and endothermic reaction.
- For exothermic reactions, heat is released. So, ΔH is positive
- For endothermic reactions, heat is absorbed. So, ΔH is negative
Given the heat of solution of KI as 20.3 kJ/mol.
Since it is positive, the reaction is exothermic and ΔH is positive
Since the heat of solution of KI is 20.3 kJ/mol, the answer to the question is a. Exothermic, ΔH is positive
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