Answer:
Heat flux = 13.92 W/m2
Rate of heat transfer throug the 3m x 3m sheet = 125.28 W
The thermal resistance of the 3x3m sheet is 0.0958 K/W
Explanation:
The rate of heat transfer through a 3m x 3m sheet of insulation can be calculated as:
![q=-k*A*\frac{\Delta T}{\Delta X}\\\\q=-0.029\frac{W}{m*K}*(3m*3m)*\frac{12K}{0.025m} =125.28W](https://tex.z-dn.net/?f=q%3D-k%2AA%2A%5Cfrac%7B%5CDelta%20T%7D%7B%5CDelta%20X%7D%5C%5C%5C%5Cq%3D-0.029%5Cfrac%7BW%7D%7Bm%2AK%7D%2A%283m%2A3m%29%2A%5Cfrac%7B12K%7D%7B0.025m%7D%20%20%3D125.28W)
The heat flux can be defined as the amount of heat flow by unit of area.
Using the previous calculation, we can estimate the heat flux:
![heat \, flux=\frac{q}{A}=\frac{125.28 W}{9 m^{2} } =13.92 W/m^{2}](https://tex.z-dn.net/?f=heat%20%5C%2C%20flux%3D%5Cfrac%7Bq%7D%7BA%7D%3D%5Cfrac%7B125.28%20W%7D%7B9%20m%5E%7B2%7D%20%7D%20%20%3D13.92%20W%2Fm%5E%7B2%7D)
It can also be calculated as:
![q/A=-k*\frac{\Delta T}{\Delta X}](https://tex.z-dn.net/?f=q%2FA%3D-k%2A%5Cfrac%7B%5CDelta%20T%7D%7B%5CDelta%20X%7D)
The thermal resistance can be expressed as
![\Delta T=R_t*Q\\R_t=\Delta T/Q=\frac{\Delta X}{k*A}](https://tex.z-dn.net/?f=%5CDelta%20T%3DR_t%2AQ%5C%5CR_t%3D%5CDelta%20T%2FQ%3D%5Cfrac%7B%5CDelta%20X%7D%7Bk%2AA%7D)
For the 3m x 3m sheet, the thermal resistance is
![R_t = \frac{\Delta X}{k*A}=\frac{0.025m}{0.029W/mK*9m^{2}}=0.0958 \, K/W](https://tex.z-dn.net/?f=R_t%20%3D%20%5Cfrac%7B%5CDelta%20X%7D%7Bk%2AA%7D%3D%5Cfrac%7B0.025m%7D%7B0.029W%2FmK%2A9m%5E%7B2%7D%7D%3D0.0958%20%5C%2C%20K%2FW)
Answer:
Altogether for both models; two red jellybeans, two white jellybeans, two black jellybeans and six blue jellybeans.
<em>Note: Since no specific color was stated for oxygen atoms, the answer assigns blue colored jellybeans to represent oxygen atoms.J</em>
Explanation:
Sodium bicarbonate, NaHCO₃ is a compound composed of one atom of sodium, one atom of hydrogen, one atom of carbon and three atoms of oxygen.
Since red jellybeans represent sodium atoms, white jellybeans represent hydrogen atoms, black jellybeans represent carbon atoms and blue jellybeans represent oxygen atoms, each of the two students will require the following number of each jellybean for their model of sodium carbonate: One red jellybean, one white jellybean, one black jellybean and three blue jellybeans.
Altogether for both models; two red jellybeans, two white jellybeans, two black jellybeans and six blue jellybeans.
Answer: The rate constant for the reaction is ![3.96\times 10^{-3}min^{-1}](https://tex.z-dn.net/?f=3.96%5Ctimes%2010%5E%7B-3%7Dmin%5E%7B-1%7D)
Explanation:
Expression for rate law for first order kinetics is given by:
![t=\frac{2.303}{k}\log\frac{a}{a-x}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B2.303%7D%7Bk%7D%5Clog%5Cfrac%7Ba%7D%7Ba-x%7D)
where,
k = rate constant
t = age of sample = 559 min
a = let initial amount of the reactant = ![2.83\times 10^{-3}](https://tex.z-dn.net/?f=2.83%5Ctimes%2010%5E%7B-3%7D)
a - x = amount left after decay process = ![3.06\times 10^{-4}](https://tex.z-dn.net/?f=3.06%5Ctimes%2010%5E%7B-4%7D)
![559min=\frac{2.303}{k}\log\frac{2.83\times 10^{-3}}{3.06\times 10^{-4}}](https://tex.z-dn.net/?f=559min%3D%5Cfrac%7B2.303%7D%7Bk%7D%5Clog%5Cfrac%7B2.83%5Ctimes%2010%5E%7B-3%7D%7D%7B3.06%5Ctimes%2010%5E%7B-4%7D%7D)
![k=\frac{2.303}{559}\log\frac{2.83\times 10^{-3}}{3.06\times 10^{-4}}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7B559%7D%5Clog%5Cfrac%7B2.83%5Ctimes%2010%5E%7B-3%7D%7D%7B3.06%5Ctimes%2010%5E%7B-4%7D%7D)
![k=3.96\times 10^{-3}min^{-1}](https://tex.z-dn.net/?f=k%3D3.96%5Ctimes%2010%5E%7B-3%7Dmin%5E%7B-1%7D)
The rate constant for the reaction is ![3.96\times 10^{-3}min^{-1}](https://tex.z-dn.net/?f=3.96%5Ctimes%2010%5E%7B-3%7Dmin%5E%7B-1%7D)
<h3>
Answer:</h3>
12.387 moles
<h3>
Explanation:</h3>
We are given;
Temperature of chlorine, T = 120°C
But, K = °C + 273.15
Therefore, T = 393.15 K
Pressure, P = 33.3 Atm
Volume, V = 12 L
We are required to calculate the number of moles of chlorine gas,
To find the number of moles we are going to use the ideal gas equation;
PV = nRT
R is the ideal gas constant, 0.082057 L.atm/mol.K
Therefore, rearranging the formula;
n = PV÷RT
Hence;
n = (33.3 atm × 12 L) ÷ (0.082057 × 393.15 K)
= 12.387 moles
Therefore, the number of moles of chlorine are 12.387 moles
The correct answer is Three. Solving the given expression we get,
2.524 g (5.1 × 106 g) ÷ (6.85 × 103 g) = 1364.47÷ (6.85 × 103 g) = 1364.47÷ 705.55 = 1.93
Here, the number of significant figures is three. Thus, the result should have three <span>significant figures.</span>