If you look it up it will give you plenty of information. This is what I found:
The valence electrons of metals move freely in this way because metals have relatively low electronegativity, or attraction to electrons. The positive metal ions form a lattice-like structure held together by all the metallic bonds. ... When nonmetals bond together, the atoms share valence electrons and do not become ions
https://www.ck12.org/c/physical-science/metallic-bond/lesson/Metallic-Bonding-MS-PS/
I think it is not possible to make cd without plastic . because except plastic no other material is so durable for making cd.
Answer:
Explanation:
1. New substances such as carbondioxide and water is formed.
2. There is evolution of gas bubbles. Gases are released.
3. There is either the absorption of energy or release of energy in form of light and energy.
4. The reaction is irreversible i.e it cannot be reversed, it is permanent once the reaction take place.
5. There is a change in both odor and smell.
A chemical change is a change where new substances are formed due to changes in the properties.
Answer:
Carbon, germanium, tin and lead.
Explanation:
The silicon is belong to the carbon family. There are five elements in carbon family carbon, silicon, germanium, tin and lead. These five elements are present in same group i.e group fourteen. The elements present in same group have same number of valance electrons.
For example.
Carbon electronic configuration:
C₆ = [He] 2s² 2p²
Silicon electronic configuration:
Si₁₄ = [Ne] 3s² 3p²
Germanium electronic configuration:
Ge₃₂ = [Ar] 3d¹⁰ 4s² 4p²
Tin electronic configuration:
Sn₅₀ = [Kr] 4d¹⁰ 5s² 5p²
Lead electronic configuration:
Pb₈₂ = [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p²
we can see that in case of all elements there are four valance electrons, which are equal to the valance electrons of silicon.
<span>Answer is: pH of solution of sodium cyanide is 11.3.
Chemical reaction 1: NaCN(aq) → CN</span>⁻(aq)
+ Na⁺<span>(aq).
Chemical reaction 2: CN</span>⁻ +
H₂O(l) ⇄ HCN(aq) + OH⁻<span>(aq).
c(NaCN) = c(CN</span>⁻<span>)
= 0.021 M.
Ka(HCN) = 4.9·10</span>⁻¹⁰<span>.
Kb(CN</span>⁻) = 10⁻¹⁴ ÷
4.9·10⁻¹⁰ = 2.04·10⁻⁵<span>.
Kb = [HCN] · [OH</span>⁻]
/ [CN⁻<span>].
[HCN] · [OH</span>⁻<span>] =
x.
[CN</span>⁻<span>] = 0.021 M - x..
2.04·10</span>⁻⁵<span> = x² / (0.021 M
- x).
Solve quadratic equation: x = [OH</span>⁻<span>] = 0.00198 M.
pOH = -log(0.00198 M) = 2.70.
pH = 14 - 2.70 = 11.3.</span>
