Answer is: thermal conduction.
<span>Thermal
conduction is the transfer of heat through physical
contact. Thermal conduction is the transfer of heat by
microscopic collisions of particles. Heat spontaneously flows from a
hotter to a colder body.
</span><span>The thermal energy of that core is transferred to the surface of the Earth and lower levels of the oceans by conduction. Water in lakes and oceans transfers heat to the surface by convection.</span>
"The reaction is exothermic and ΔH is negative" can be understood about the reaction and the enthalpy change (ΔH) during the reaction.
<u>Option: D</u>
<u>Explanation:</u>
When the reaction is positive, the process becomes endothermic, i.e. heat appears to be consumed by the system because the reaction products are more enthalpic than the reactants. When the reaction is negative, on the other hand, the process is exothermic, which is the total decrease in enthalpy is caused by heat production. Here the initial temperature is 21.0 C but increase in final temperature to 38.8 C, because if some processes require heat, others must give off heat when they take place.
The independent variable in the experiment is the soap and the dependent variable in the experiment is the number of water drops on the surface of the penny. The control is the penny without soap.
3K + AlCl3 --------> 3 KCl + Al
element compound compound element
This is single replacement (displacement) reaction.
The pH = 2.41
<h3>Further explanation</h3>
Given
5.0% by mass solution of acetic acid
the density of white vinegar is 1.007 g/cm3
Required
pH
Solution
Molarity of solution :
Ka for acetic acid = 1.8 x 10⁻⁵
[H⁺] for weak acid :
![\tt [H^+]=\sqrt{Ka.M}](https://tex.z-dn.net/?f=%5Ctt%20%5BH%5E%2B%5D%3D%5Csqrt%7BKa.M%7D)
Input the value :
![\tt [H^+]=\sqrt{1.8\times 10^{-5}\times 0.839}\\\\(H^+]=0.00388=3.88\times 10^{-3}\\\\pH=3-log~3.88=2.41](https://tex.z-dn.net/?f=%5Ctt%20%5BH%5E%2B%5D%3D%5Csqrt%7B1.8%5Ctimes%2010%5E%7B-5%7D%5Ctimes%200.839%7D%5C%5C%5C%5C%28H%5E%2B%5D%3D0.00388%3D3.88%5Ctimes%2010%5E%7B-3%7D%5C%5C%5C%5CpH%3D3-log~3.88%3D2.41)
