Answer:
Energy produced by the chip =10,460 Joules.
Explanation:
The specific heat of water is one calorie/gram ° C = 4.186 joules/gram ° C, which is higher than any other common substance. As a result, water plays a very important role in regulating temperature. The specific heat per gram for water is much greater than that of a metal, as described in the water-metal example. Replace the mass (m), the temperature change (ΔT), and the specific heat (c) of the solution in the equation Q = c x m x ΔT, where Q is the heat absorbed by the solution. For specific heat of water we goes as given in the question 4,184 J/kg°C
Q =4184×0.5×(25-20)
=10,460 Joules.
Thus heat gained by water (Q)= Energy produced by the chip =10,460 Joules.
Solid KMnO₄ needed = 7.9 g
<h3>Further explanation</h3>
Given
MW KMnO₄ = 158 g/mol
500 mL(0.5 L) of a 0.1M stock solution of KMnO₄
Required
solid KMnO₄
Solution
Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution

Input the value :
n = M x V
n = 0.1 M x 0.5 L
n = 0.05 mol
Mass KMnO₄ :
= mol x MW
= 0.05 x 158 g/mol
= 7.9 g