Which substance has a molar mass of 142 g?

 alcl3

bacl2

mgcl2

p2o5

Molar mass of P₂O₅ = 141.948 g/mol which is approximately 142 g/mol.

Explanation:

Molar mass of AlCl₃

Molar mass  = 26.982 + 35.5 × 3 = 133.32 g/mol

Molar mass of BaCl₂

Molar mass  = 137.33 + 35.5 × 2 = 208.33 g/mol

Molar mass of MgCl₂

Molar mass  = 24.305 + 35.5×2 = 95.305 g/mol

Molar mass of P₂O₅

Molar mass  = 30.974×2 + 16× 5 = 141.948 g/mol

i think a, hope it .

explanation:

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm