First find the oxidation states of the various atoms:
<span>in Cr2O2 2- Cr @ +1; In NH3 N @ +3; in CrO3 Cr @ +3, N2 N @ 0 </span>
<span>Note that N gained electrons, ie, was reduced; Cr was oxidized </span>
<span>Now there is a problem, because B has NH4+ which the problem did not, and is not balanced, showing e- in/out </span>
<span>B.NH4+ → N2 </span>
<span>Which of the following is an oxidation half-reaction? </span>
<span>A.Sn 2+ →Sn 4+ + 2e- </span>
<span>Sn lost electrons so it got oxidized</span>
The answer is , C. Both the atomic mass and the atomic number increase from left to right .
Number of Carbon atoms = 3*1 + 1 = 3 + 1 = 4
In short, Your Answer would be Option B
Hope this helps!
Answer:
The molar mass of the vapor is 43.83 g/mol
Explanation:
Given volume of gas = V = 247.3 mL = 0.2473 L
Temperature = T = 100
= 373 K
Pressure of the gas = P = 745 mmHg (1 atm = 760 mmHg)

Mass of vapor = 0.347 g
Assuming molar mass of gas to be M g/mol
The ideal gas equation is shown below

The molar mass of the vapor comes out to be 43.834 g/mol
Mole fraction is a unit of concentration, defined to be equal to the number of moles of a component divided by the total number of moles of a solution. Because it is a ratio, mole fraction is a unitless expression. The mole fraction of all components of a solution, when added together, will equal 1.