Answer:
- <u><em>The leftover reactant is the nitrogen gas, N₂.</em></u>
Explanation:
As per your description:
<u>1. Square on the left: N₂(g)</u>
- 3 units of two joint circles: this represents 3 molecules of nitrogen gas, N₂(g).
<u>2. Square on the right: H₂(g)</u>
- 3 units of two joint circles: this represents 3 molecules of hydrogen gas, H₂(g).
<u>3. Reaction</u>
If the maximum possible amount of NH₃ is formed during the reaction, you assume that the reaction goes to completion.
The chemical equation that represents the reaction is:
Which must be balanced:
That means that 1 molecule (or 1 mol) of N₂(g) reacts with 3 molecules (or 3 moles ) of H₂(g) to produce 2 molecules (or 2 moles) of NH₃(g).
Since, the squares show that there are 3 molecules of each reactant, the 3 molecules of hydrogen gas will be able to react with 1 molecule of nitrogen gas. When that happens, all the hydrogen gas is consumend and yet two molecules of nitrogen gas will remain unreacted. Hence, the nitrogen gas is the leftover reactant.
Acetaminophen as a chemical formula of C8H9NO2. The molar
masses are:
C8H9NO2 = 151.163 g/mol
C = 12 g/mol
H = 1 g/mol
N = 14 g/mol
O = 16 g/mol
<span>TO get the mass percent, simply multiply the molar mass of
each elements with the number of the
element divide by the molar mass of acetaminophen, that is:</span>
%C = [(12 * 8) / 151.163] * 100% = 63.50%
%H = [(1 * 9) / 151.163] * 100% = 5.954%
%N = [(14 * 1) / 151.163] * 100% = 9.262%
<span>%O = [(16 * 2) / 151.163] * 100% = 21.17% </span>
Answer: Reaction 1 is non spontaneous.
Explanation:
According to Gibb's equation:
= Gibbs free energy
= enthalpy change
= entropy change
T = temperature in Kelvin
When = +ve, reaction is non spontaneous
= -ve, reaction is spontaneous
= 0, reaction is in equilibrium
For the given reaction 1: 
As for the reaction 1 , the value of Gibbs free energy is positive and thus the reaction 1 is non spontaneous.
Answer:
Na₂CO₃.2H₂O
Explanation:
For the hydrated compound, let us denote is by Na₂CO₃.xH₂O
The unknown is the value of x which is the amount of water of crystallisation.
Given values:
Starting mass of hydrate i.e Na₂CO₃.xH₂O = 4.31g
Mass after heating (Na₂CO₃) = 3.22g
Mass of the water of crystallisation = (4.31-3.22)g = 1.09g
To determine the integer x, we find the number of moles of the anhydrous Na₂CO₃ and that of the water of crystallisation:
Number of moles = 
Molar mass of Na₂CO₃ =[(23x2) + 12 + (16x3)] = 106gmol⁻¹
Molar mass of H₂O = [(1x2) + (16)] = 18gmol⁻¹
Number of moles of Na₂CO₃ = 
= 0.03mole
Number of moles of H₂O = 
= 0.06mole
From the obtained number of moles:
Na₂CO₃ H₂O
0.03 0.06
Simplest
Ratio 0.03/0.03 0.03/0.06
1 2
Therefore, x = 2
