Answer:
Explanation:
A radioactive isotope is an isotope that undergoes nuclear decay, breaking apart into a smaller nucleus and emitting radiation during the process.
The half-life of an isotope is the amount of time it takes for a certain quantity of a radioactive isotope to halve.
For a radioactive isotope, the amount of substance left after a certain time t is:
(1)
where
is the mass of the substance at time t = 0
m(t) is the mass of the substance at time t
is the half-life of the isotope
In this problem, the isotope is uranium-235, which has a half-life of
We also know that the amount of uranium left in the rock sample is 6.25% of its original value, this means that
Substituting into (1) and solving for t, we can find how much time has passed:
They split in half making there more atoms
Answer:
B.) No, because the coefficients could be reduced to 2,1, and 3.
Explanation:
The equation is not in its lowest molar ratio form. In this case, all of the coefficients can be divided by 2 and still result in whole numbers.
As such, the correct balanced equation is:
2 NH₃ ----> N₂ + 3 H₂
<span>rusting takes a long time, and rusting is a chemical change.</span>
Answer:
The new pressure will be 1.86 atm.
Explanation:
As the volume increases, the gas particles (atoms or molecules) take longer to reach the walls of the container and therefore collide less times per unit time against them. This means that the pressure will be less because it represents the frequency of gas strikes against the walls. In this way pressure and volume are related, determining Boyle's law.
Boyle's law says that at constant temperature, the volume of a fixed mass of gas is inversely proportional to the pressure it exerts:
P*V=k
To determine the change in pressure or pressure during a transformation to constant pressure, the following expression is applied:
P1*V1=P2*V2
In this case:
- P1= 0.62 atm
- V1= 3 L
- P2= ?
- V2= 1 L
Replacing:
0.62 atm* 3L= P2* 1 L
Solving:
P2= 1.86 atm
<u><em>The new pressure will be 1.86 atm.</em></u>
