Answer:
B
Explanation:
If the temperature of the water goes up, the reaction is exothermic (heat is being given away by the equation -- more precisely the reactants of the equation). Only A and B can be true. In order for the reaction to occur, the water has to absorb the heat. It's temperature goes up. Remember that minus sign. It is almost the key fact for this question.
The question is not as hard as it looks, but that is easy for me to say.
m = 100 g
c = 4.2 J/(g * oC)
deltaT = 21 - 20 degrees = 1 degree.
Heat = 100 * 4.2 * 1
Heat = 420 J
Heat = 420 * [1 kJ/1000 J]
Heat = -0.42 kJ
B
The model of the solar system is way smaller than the real object. The model of sub-atomic particles in a atom is way larger than the real object.
0.0857
Rounding off to three digits
Since 7 is more than five you change it to 0 and add 1 to 5
A: 0.086
The maximum radiation pressure exerted by sunlight in space on a flat black surface is 4.5 ×
P a. So, the correct option is (b).
Radiation pressure is the name for the force electromagnetic wave particles exert on a surface. It is inversely related to the wave's speed. Given data
Solar constant ( S ) = 1350W / m ^2
Now, the radiaton pressure is given by
P = 2 S /c
where c is the speed of the light
P = 2 × 1350 /3 × 10 ^8
P = 9 ×
P a
For a black surface, P = 4.5×
P a
Therefore, maximum radiation pressure exerted by sunlight in space on a flat black surface is 4.5 ×
P a
Learn more about radiation pressure here;
brainly.com/question/23972862
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