Answer: 29.0 years
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
b) for decomposition of 80 % of reactant
The age of a suspected vintage wine that is 20 % as radioactive as a freshlybottled specimen is 29.0 years
Answer:
<h2>2.54 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>2.54 moles</h3>
Hope this helps you
Answer:
-3.617 °C
Explanation:
Step 1: Given data
Mass of water (m): 210.0 g
Energy released in the form of heat (Q): -3178 J (the minus sign corresponds to energy being released)
Specific heat of water (c): 4.184 J/g.°C
Temperature change (ΔT): ?
Step 2: Calculate the temperature change
We will use the following expression.
Q = c × m × ΔT
-3178 J = 4.184 J/g.°C × 210.0 g × ΔT
ΔT = -3.617 °C
Chemical potential energy: chemical potential of a species is energy that can be absorbed or released due to a change of the particle number of the given species, in a chemical reaction or phase transition
Gasoline used as kinetic energy: the various chemicals that make up gasoline contain a large amount of chemical potential energy that is released when the gasoline is burned in a controlled way in the engine of the car. The release of that energy does two things. Some of the potential energy is transformed into work, which is used to move the car
Dynamite used as kinetic energy: the dynamite being used was most likely made of nitroglycerin. Once the dynamite explodes from a percussion force (then breaking of weak bonds to releasing the raw atom) the energy is then converted to thermal, kinetic, and sound energy.
