Explanation:
Specific heat capacity of gold (S)
= 0.126 J /kg°C
mass (m) = 350 g = 0.35 kg
difference in temperature (dt)
= 88.5°C - 24.6°C
= 63.9° C
Now
Energy released (Q)
= m*s*dt
= 0.35 * 0.126 * 63.9
= 2.81799 Joule
Hope it will help :)
Answer:
chemical knowledge
Explanation:
The pursuit of chemical knowledge for its own sake, no set goal Applied chemistry Research that is directed toward a practical goal or application, geared toward a specific goal
Bromocresol purple has a change in color from yellow, which is the acid form and purple, which is the basic form:
Bromocresol purple:
HIn + H₂O ⇄ In⁻ + H₃O⁺
yellow Purple
After you make all of the experiment you should obtain a graph similar to the one given to you in the practice guide. Like the attached image:
To select the wavelength of maximum absorbance for the pH < 4.0 solution pick the line of the graph traced at pH 4. This line has a curvature with a maximum around 450 nm (look more closely in your graph). the color in this case is yellow.
To find the wavelength of maximum absorbance for the pH > 10.0 solution pick now the line traced for the solution at pH 10. the maximum curvature should be around 590 nm. The color for this wavelength is purple.
For the last question: How do the observed colors of these solutions relate to the colors at their absorbance maxima? the colors that we are observing are complementary to the color that we are measuring as the absorption wavelength. This is to say, 590 nm is the wavelength of the red color. since the red tone is the one absorbed, the color reflected is the one we see, the complement. The same happens with the yellow. Yellow is a complementary color of the wavelength that is being absorbed.
Answer:
Option B. 2096.1 K
Explanation:
Data obtained from the question include the following:
Enthalpy (H) = +1287 kJmol¯¹ = +1287000 Jmol¯¹
Entropy (S) = +614 JK¯¹mol¯¹
Temperature (T) =.?
Entropy is related to enthalphy and temperature by the following equation:
Change in entropy (ΔS) = change in enthalphy (ΔH) / Temperature (T)
ΔS = ΔH / T
With the above formula, we can obtain the temperature at which the reaction will be feasible as follow:
ΔS = ΔH / T
614 = 1287000/ T
Cross multiply
614 x T = 1287000
Divide both side by 614
T = 1287000/614
T = 2096.1 K
Therefore, the temperature at which the reaction will be feasible is 2096.1 K
Mole number of 75 g is 0.4 mol. NO2 is 0.8 mol and is 36.8 g.