Answer:
The heat of reaction when hydrogen and oxygen combine to form water is :
<u>C. 571.6 kJ</u>
Explanation:
Enthalpy Change = The enthalpy change for the formation of 1 mole of the substance from their standard state is called the enthalpy of formation.
This is intensive quantity as it is fixed for 1 mole .
Intensive properties = Those properties which are independent on the amount of the substance are intensive properties.
The value of these quantities does not get halve if you divide the substance into two equal parts. example , density, refractive index.
However , the enthalpy of reaction is extensive. Because on increasing the amount the value of the enthalpy also get doubles
Hence for this reaction :
Its value is -285.8 kJ for 1 mole
And here two moles are present . so the value of molar enthalpy is:
-285.8 x 2 = -571.6 kJ
Answer: Rate of decomposition of acetaldehyde in a solution is 
Explanation:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
For a reaction : 
![Rate=k[A]^x](https://tex.z-dn.net/?f=Rate%3Dk%5BA%5D%5Ex)
k= rate constant
x = order of the reaction = 2
Thus rate of decomposition of acetaldehyde in a solution is
The phosphate concentration of the unknown sample is <u>0.002 M</u>
<u />
Beer's law, the quantity of power absorbed or transmitted by using a solution is proportional to the solution's molar absorptivity and the awareness of the solute. In easy terms, a greater focused answer absorbs greater light than a more dilute solution does.
C = εa/b
= 0.285 / 137.2
=<u> 0.002 M</u>
A sequence of fashionable solutions containing a purple dye was made by diluting an inventory answer and then measuring the percent transmittance of every answer at 505 nm (greenish blue). This wavelength became decided on with the aid of examining its absorption spectrum.
Lambert's law of absorption states that equal elements inside the equal absorbing medium soak up identical fractions of the mild that enters them. If in traversing a path of duration dx the intensity is decreased.
Learn more about beer's law here:-brainly.com/question/18591932
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