physics 2B---- A toy balloon is filled with helium gas ( He}) at 1atm} and 30 degrees Celcius. If the volume of the balloon is 0.025 m^3, how many atoms does it contain?

This ties in with chemistry actually. They give you Temperature, Pressure, and Volume. Convert temperature to Kelvins (add 273) and convert your volume to Liters. Use R constant 0.0821. Plug into the ideal gas law of PV=nRT and solve for the moles of the He atom (thats n). Once you have moles, its a simple conversion, 1 mole= atoms of 6.022x10^23. So it'd be your molesx 6.022x10^23 atoms/1 mole.

THANKS!JUST HAD TO FIND THE R CONSTANT VALUE: 8.3145J/MOL

To find the number of atoms in the balloon, we need to use the ideal gas law equation.

The ideal gas law equation is given as:

PV = nRT

Where:
P is the pressure of the gas (in pascals)
V is the volume of the gas (in cubic meters)
n is the number of moles of gas
R is the ideal gas constant (8.314 J/(mol·K))
T is the temperature of the gas (in kelvin)

First, we need to convert the pressure from atm to pascals. 1 atmosphere is equal to 101325 pascals.

1 atm = 101325 Pa

Next, we need to convert the temperature from Celsius to Kelvin. The temperature in Kelvin is obtained by adding 273.15 to the temperature in Celsius.

T(in Kelvin) = T(in Celsius) + 273.15

Now, we can rearrange the ideal gas law equation to solve for the number of moles.

n = PV / RT

Let's plug in the values:

P = 1 atm = 101325 Pa
V = 0.025 m^3
R = 8.314 J/(mol·K)
T = 30°C + 273.15 = 303.15 K

n = (101325 Pa) * (0.025 m^3) / (8.314 J/(mol·K) * 303.15 K)

Now, we can calculate the value of n.

n ≈ 1.04 moles

Finally, to find the number of atoms, we use Avogadro's number, which states that there are 6.022 × 10^23 atoms in one mole of a substance.

Number of atoms = n * Avogadro's number

Number of atoms ≈ 1.04 moles * 6.022 × 10^23 atoms/mole

Number of atoms ≈ 6.27 × 10^23 atoms

Therefore, the toy balloon contains approximately 6.27 × 10^23 atoms.