Wax is definitely susceptible to heat and with the application of heat such as burning a candle, the solid wax gets converted into a liquid. This fact can be used to remove ear wax also actually using hollow candles that will melt the ear wax and allow it to be drained out of the ear.
Answer:
Explanation:
The oxidation number is an integer that represents the number of electrons that an atom receives or makes available to others when it forms a given compound.
The oxidation number is positive if the atom loses electrons, or shares them with an atom that has a tendency to accept them. And it will be negative when the atom gains electrons, or shares them with an atom that has a tendency to give them up.
Chemical compounds are electrically neutral. That is, the charge that all the atoms of a compound contribute must be globally null. That is, when having positive or negative charges in a compound, their sum must be zero.
There are some rules for determining oxidation numbers in compounds. Among them it is possible to mention:
- Hydrogen (H) has an oxidation number +1 with nonmetals and - 1 with metals.
- Oxygen (O) presents the oxidation number -2
- Fluorine F has a unique oxidation state -1
Then:
- NOF: N+(-2)+(-1)=0 → N=3 → oxidation number of nitrogen (N) is +3, oxidation number of oxygen (O) is -2 and oxidation number of fluorine (F) is -1.
- ClF₅: Cl + 5*(-1)=0 → Cl= 5 → oxidation number of chlorine (Cl) is +5 and oxidation number of fluorine (F) is -1.
- H₂SO₃: 2*(+1)+S+3*(-2)=0 → S=4 → oxidation number of hydrogen (H) is +1, oxidation number of oxygen (O) is -2 and oxidation number of sulfur (S) is +4.
Answer:
Carbonyl
Explanation:
While the diagram is slightly unclear, the molecule most likely being shown is a carbonyl. A molecule is a carbonyl when there is a carbon double-bonded to an oxygen.
Answer:
(a) The system does work on the surroundings.
(b) The surroundings do work on the system.
(c) The system does work on the surroundings.
(d) No work is done.
Explanation:
The work (W) done in a chemical reaction can be calculated using the following expression:
W = -R.T.Δn(g)
where,
R is the ideal gas constant
T is the absolute temperature
Δn(g) is the difference between the gaseous moles of products and the gaseous moles of reactants
R and T are always positive.
- If Δn(g) > 0, W < 0, which means that the system does work on the surroundings.
- If Δn(g) < 0, W > 0, which means that the surroundings do work on the system.
- If Δn(g) = 0, W = 0, which means that no work is done.
<em>(a) Hg(l) ⇒ Hg(g)</em>
Δn(g) = 1 - 0 = 1. W < 0. The system does work on the surroundings.
<em>(b) 3 O₂(g) ⇒ 2 O₃(g)
</em>
Δn(g) = 2 - 3 = -1. W > 0. The surroundings do work on the system.
<em>(c) CuSO₄.5H₂O(s) ⇒ CuSO₄(s) + 5H₅O(g)
</em>
Δn(g) = 5 - 0 = 5. W < 0. The system does work on the surroundings.
<em>(d) H₂(g) + F₂(g) ⇒ 2 HF(g)</em>
Δn(g) = 2 - 2 = 0. W = 0. No work is done.
