An unknown gas at 130 celsius has a rms speed that is 0.50 that of the rms speed of N2 molecules at 50 degrees celsius. What is the molecular weight of unknown gas?

M = 613.8455 kg/mol

Explanation:

RMS velocity or root mean square velocity has a formula for particles:

RMS = (3*R*T/ M)^ (1/2)

Where R is the ideal gas constant = 8.314 (kg*m^2 / s^2)/ K*mol

T is the temperature in Kelvin

M is the mass of a mole of the gas in kilograms (kg)

1) Convert the temperature to Kelvin for the N2 particles

T = *C +273  

T = 50 + 273

T = 323 K

2) Find the molar mass of the particles in kg for N2

using the periodic table: Nitrogen (N) molar mass is 14.00667 g/mol

N2 molar mass = 2 * 14.00667 = 28.01334 g/mol

Convert to kg/mol using dimensional analysis and conversion factor of 1 kg = 1000 g

28.01334 g / mol * 1 kg / 1000 g = 0.02801334 kg/mol

4) find the RMS of N2

RMS = (3 * (8.314 (kg*m^2 / s^2)/K*mol) * (323K) / 0.02801334 kg/mol))^1/2

=536.2712 m/s

5)If we take 0.5 of N2 RMS or 1/2 we get: 268.1356 m/s for the RMS of the unknown gas

6) Rearrange the equation to solve for M

RMS=(3RT/M)^1/2

Solve for M

We know that a^(1/2) = sqrt(a)

sqrt(RMS) = (3RT/M)

sqrt(RMS) * M = 3RT

M = 3RT / sqrt(RMS)

5) Change the temperature to Kelvins

T = 130 +273 = 403 K

6) Plug the numbers in and solve for M

M = (3*(8.314 (kg*m^2 / s^2)/K*mol) * (403 K)) / sqrt(268.1356 m/s)

M = 613.8455 kg/mol

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.