Answer:
1813.74g
Explanation:
Given parameters:
Number of moles of radon = 8.17moles
Unknown:
Mass of radon = ?
Solution:
To solve this problem, we use the expression below:
Number of moles = 
Molar mass of radon = 222g/mol
Now insert the parameters and solve;
Mass of radon = Number of moles x molar mass
= 8.17 x 222
= 1813.74g
Answer:
B. temperature decreases as altitude increases.
Explanation:
Just like in the lower reaches of the atmosphere, the troposphere, in the mesosphere, temperature decreases as altitude increases.
The mesosphere is the third layer of the atmosphere just above the stratosphere.
- It begins at the top of the stratosphere and ends at the mesopause where the thermosphere begins.
- The mesosphere is often referred to as the middle layer.
With increasing height, the temperature of the mesosphere decreases significantly. The top of the mesosphere is one of the coldest part of the earth atmosphere. This is as a result of increasing atmospheric cooling by carbon dioxide in this region of the atmosphere.
Nucleic Acids are polymers made of nucleotideds
Answer:
75 kJ/mol
Explanation:
The reactions occur at a rate, which means that the concentration of the reagents decays at a time. The rate law is a function of the concentrations and of the rate constant (k) which depends on the temperature of the reaction.
The activation energy (Ea) is the minimum energy that the reagents must have so the reaction will happen. The rate constant is related to the activation energy by the Arrhenius equation:
ln(k) = ln(A) -Ea/RT
Where A is a constant of the reaction, which doesn't depend on the temperature, R is the gas constant (8.314 J/mol.K), and T is the temperature. So, for two different temperatures, if we make the difference between the two equations:
ln(k1) - ln(k2) = ln(A) - Ea/RT1 - ln(A) + Ea/RT2
ln (k1/k2) = (Ea/R)*(1/T2 - 1/T1)
k1 = 8.3x10⁸, T1 = 142.0°C = 415 K
k2 = 6.9x10⁶, T2 = 67.0°C = 340 K
ln(8.3x10⁸/6.9x10⁶) = (Ea/8.314)*(1/340 - 1/415)
4.8 = 6.39x10⁻⁵Ea
Ea = 75078 J/mol
Ea = 75 kJ/mol
