C) The molecules of a gas are much further
apart than those of a solid.
In photograph a, a coil of zinc metal is in a solution of sulfuric acid. In photograph b, a yellow solution of sodium chromate is being added to a colorless solution of silver nitrate. What clues in the photographs indicate that a chemical change is probably occurring.
In photograph a, chemical change is occuring as when a coil of zinc metal is in a solution of sulfuric acid, then the solution starts bubbling, that indicates a chemical change.
In photograph b, a yellow solution of sodium chromate is being added to a colorless solution of silver nitrate, that changes the color of the solution to red , that indicates a chemical change.
The temperature of the nitrogen gas is 292.5 K.
<u>Explanation:</u>
Given that
Moles of Nitrogen, n = 5 mol
Volume, V = 30 L
Pressure, P = 4 atm
Gas Constant, R = 0.08205 L atm mol⁻¹ K⁻¹
Temperature = ? K
We have to use the ideal gas equation,
PV = nRT
by rearranging the equation, so that the equation becomes,
T = 
Plugin the above values, we will get,
T = 
= 292.5 K
So the temperature of the nitrogen gas is 292.5 K.