Achemist isolated a gas in a glass bulb with a volume of 255 ml at a temperature of 25 and a pressure of 10 torr. the gas weighed 12.1 mg. what is the molecular mass of this gas

88.5 g/m is the molar mass for the gas

Explanation:

We need the Ideal Gases Law equation to solve this:

P . V = n . R . T

Pressure (P) = 10 Torr

We must convert to atm → 10 Torr / 760 Torr = 0.0131 atm

Volume (V) = 255 mL

We must convert to L → 255 mL /  1000 = 0.255 L

n = number of moles

moles = mass in g / molar mass

12.1 mg/ 1000 = 0.0121 g

T° = 25°C + 273K = 298K

R = 0.082 L.atm /mol.K

Let's replace the values

0.0131 atm . 0.255L = 0.0121 g / x .  0.082 L.atm /mol.K  . 298K

(0.0131 atm . 0.255L) / (0.082 L.atm /mol.K  . 298K) = 0.0121 g / x

1.367×10⁻⁴ /mol = 0.0121 g / x

x = 0.0121 g / 1.367×10⁻⁴ mol = 88.5 g/m

explanation:

i think option no d is the correct answer

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-