The general equation for radioactive decay is;
N = N₀e^(-λt)
x - decay constant (λ) - rate of decay
t- time
N - amount remaining after t days , since we are calculating the half life, amount of time it takes for the substance to to be half its original value, its N₀/2
N₀ - amount initially present
substituting the values
N₀/2 = N₀e^(-0.081t)
0.5 = e^(-0.081t)
ln (0.5) = -0.081t
-0.693 = -0.081t
t = 0.693 / 0.081
= 8.55
half life of substance is 8.55 days
<u>Answer:</u> The correct answer is Option B.
<u>Explanation:</u>
Decomposition is a type of chemical reaction in which larger compound breaks down into two or more smaller compounds.

Double displacement reactions is defined as the chemical reaction in which exchange of ions takes place.

Synthesis reaction is a type of reaction in which two or more smaller compounds combines to form a single large compound.

Single displacement reaction is a type of reaction in which a more reactive metal displaces a less reactive metal from its chemical reaction.

In stomach, an acid is present known as hydrochloric acid and to neutralize its effect, antacid is taken which has
as a component.
The reaction between HCl and
is a type of neutralization reaction and it is a type of double displacement reaction.
The equation between the two follows:

Hence, the correct answer is Option B.
Answer:- HBr is limiting reactant.
Solution:- The given balanced equation is:

From this equation, There is 2:6 mol or 1:3 mol ratio between Al and HBr. Since we have 8 moles of each, HBr is the limiting reactant as we need 3 moles of HBr for each mol of Al.
The calculations could be shown as:

= 24 mol HBr
From calculations, 24 moles of HBr are required to react completely with 8 moles of Al but only 8 moles of it are available. It clearly indicates, HBr is limiting reactant.
Answer:
Thermodynamics is the branch of physics that deals with the relationships between heat and other forms of energy.