Answer:
18857.553
Explanation:
for an approximate result, multiply the value by 239
Answer:
Group 2
Explanation:
Because group 2 is very reactive and forms salts with other non metals. Example Calcium Chloride. Calcium is from group 2, forms ionic salts with other non metal, and exists as solid at standard temp and pressure.
Answer: The half-life of a first-order reaction is, 
Explanation:
All the radioactive reactions follows first order kinetics.
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 = 440 s
= initial amount of the reactant = 0.50 M
[A] = left amount = 0.20 M
Putting values in above equation, we get:


The equation used to calculate half life for first order kinetics:

Putting values in this equation, we get:

Therefore, the half-life of a first-order reaction is, 
Answer:
D. release of carbon dioxide on heating limestone