47. a student constructs a model for comparing
the masses of subatomic particles. the
student selects a small, metal sphere with
a mass of 1 gram to represent an electron.
a sphere with which mass would be most
appropriate to represent a proton?
(1)1g (3) 20008
(4) 2000 g 47
09

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.

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.

what is the question here. i think you messed up.

answer: i dont know the answer but this might

explanation:

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