A sperical ballon with a diameter of 6 m filled with helium at 20 degree centigrade and 200kpa determine mole number and the mass of helium ​

A. 9280.78 moles.

B. 37123.12 g.

Explanation:

We'll begin by calculating the volume of the spherical balloon. This can be obtained as follow:

Diameter (d) = 6 m

Radius (r) = d/2 = 6/2 = 3 m

Pi (π) =3.14

Volume (V) =?

V = 4/3πr³

V = 4/3 × 3.14 × 3³

V = 4/3 × 3.14 × 27

V = 113.04 m³

Next, we shall convert 20°C to Kelvin temperature. This can be obtained as follow:

T(K) = T(°C) + 273

T(°C) = 20°C

T(K) = 20°C + 273

T(K) = 293 K

Next, we shall convert 200 KPa to Pa. This can be obtained as follow:

1 KPa = 1000 Pa

Therefore,

200 KPa = 200 KPa × 1000 Pa / 1 KPa

200 KPa = 2×10⁵ Pa

A. Determination of the number of mole of He in the spherical balloon.

Volume (V) = 113.04 m³

Temperature (T) = 293 K

Pressure (P) = 2×10⁵ Pa

Gas constant (R) = 8.314 m³Pa/Kmol

Number of mole (n) =?

PV = nRT

2×10⁵ × 113.04 = n × 8.314 × 293

22608000 = n × 2436.002

Divide both side by 2436.002

n = 22608000 / 2436.002

n = 9280.78 moles

B. Determination of the mass of He.

Mole of He (n) = 9280.78 moles

Molar mass of He = 4 g/mol

Mass of He =?

Mass = mole × molar mass

Mass of He = 9280.78 × 4

Mass of He = 37123.12 g

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.