A chemical change is characterized of the formation of new substances or a chemical reaction. There are a number of observations that we can see if this type of change happens. One would be the formation of gas bubbles, this indicates that one of the products is a gas. Another observation would be a formation of a precipitate in the solution, it would indicate that the new solid formed is not soluble in the solution. A permanent color change in the solution would also indicate a chemical change because it may be that the new substance that is formed has its own distinct color when in solution.
Answer:
It is a molecular compound.
Explanation:
Answer:
Its a small dense spherical structure in the nucleus of a cell during interphase.
Answer:
ΔH° = 206.1 kJ
ΔG° = 142.1 kJ
Explanation:
Let's consider the first step in the synthesis of methanol.
Step 1: CH₄(g) + H₂O(g) ⟶ CO(g) + 3 H₂(g) ΔS° = 214.7 J / K
We can calculate the standard enthalpy of the reaction (ΔH°) using the following expression.
ΔH° = ∑np . ΔH°f(p) - ∑nr . ΔH°f(r)
where,
ni are the moles of reactants and products
ΔH°f(p) are the standard enthalpies of formation of reactants and products
ΔH° = [1 mol × ΔH°f(CO(g)) + 3 mol × ΔH°f(H₂(g))] - [1 mol × ΔH°f(CH₄(g)) + 1 mol × ΔH°f(H₂O(g))]
ΔH° = [1 mol × (-110.5 kJ/mol) + 3 mol × (0 kJ/mol)] - [1 mol × (-74.81 kJ/mol) + 1 mol × (-241.8 kJ/mol)]
ΔH° = 206.1 kJ
We can calculate the standard Gibbs free energy (ΔG°) using the following expression.
ΔG° = ΔH° - T.ΔS°
ΔG° = 206.1 kJ - 298 K × (214.7 × 10⁻³ kJ/K)
ΔG° = 142.1 kJ