<u>Answer:</u> The equation to calculate the mass of remaining isotope is ![[A]=\frac{20}{10^{-0.217t}}](https://tex.z-dn.net/?f=%5BA%5D%3D%5Cfrac%7B20%7D%7B10%5E%7B-0.217t%7D%7D)
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:
where,
= half life of the reaction = 
Putting values in above equation, we get:
Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount of the sample = 20 grams
[A] = amount left after decay process = ? grams
Putting values in above equation, we get:
![0.5=\frac{2.303}{t}\log\frac{20}{[A]}](https://tex.z-dn.net/?f=0.5%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B20%7D%7B%5BA%5D%7D)
Hence, the equation to calculate the mass of remaining isotope is
Answer:
D. Water and Carbondioxide
Explanation:
Combustion of organic compounds in the presence of excess Oxygen will liberate carbondioxide (CO2) and water vapour (H2O). This is an exothermic reaction because heat is liberated to the surroundings.
CnH2n+1OH(aq) + (3/2*n)O2(g) --> nCO2(g) + (n + 1)H2O(g)
Addition of Oxygen can also be termed as a redox reaction. In this case, alcohols are oxidised while the Oxygen is reduced.
Example, (propanol)
C3H7OH(aq) + 9/2O2(g) --> 3CO2(g) + 4H2O(g)
The answer is B.) 3
Because Segment 2 shows the condensation of water from the gas phase to the liquid phase. <u>It is during this segment that liquid water first appears.</u> Therefore, after 3 minutes, liquid water first appears.
