I guess the correct answer is the first one.
Answer:
525 Bq
Explanation:
The decay rate is directly proportional to the amount of radioisotope, so we can use the half-life equation:
A = A₀ (½)^(t / T)
A is the final amount
A₀ is the initial amount,
t is the time,
T is the half life
A = (8400 Bq) (½)^(18.0 min / 4.50 min)
A = (8400 Bq) (½)^4
A = (8400 Bq) (1/16)
A = 525 Bq
Complete question:
A volume V= 2.48 L of an ideal nitrogen gas (N2) are at temperature T= 0.964°C and pressure p = 1.49 atm. Find the number of moles of the gas.
Answer:
The number of mole of the gas is 0.164 mol.
Explanation:
Given;
volume of the ideal gas, V = 2.48 L
temperature of the gas, T = 0.964 °C = 273K + 0.964 = 273.964 K
pressure of the gas, P = 1.49 atm
The number of moles of the gas is calculated by using ideal gas equation;
PV = nRT
where;
n is the number of moles of the gas
R is ideal gas constant = 0.082057 L.atm/mol.K
Therefore, the number of mole of the gas is 0.164 mol.
Answer:
A motion produced by electric charge which causes attractive and repulsive forces between objects.
In a series circuit . . .
There is only one path for current to take.
All the way from one terminal of the power supply, through all of
the lights, computers, vending machines, air conditioners and
everything else in the building, to the other terminal of the electric
supply. One path !
So the current for EVERY device has to flow through ALL of them,
because that's the only path there is.
If any ONE device in the building was turned off, burned out, or
unplugged from the outlet, then there would be NO PATH for the
current, and everything in the building would lose power !
Not a very convenient way to operate a house or a building.
