24. <span>Valence electrons are most loosely held by the atom and are involved in chemical reactions. Chemical reactions occur when valence electrons are shared between atoms. The number of valence electrons determines how these reactions take place and what kind of bonds they form.
25 </span><span>Sodium has one valence electron and chlorine has seven valence electrons. The Ione valence electron from sodium is lost and is transferred to the chlorine atom. The result is a sodium ion with a charge of 1+ and a chloride ion with a charge of 1-. The oppositely charged ions attract each other and the charges balance to make a compound that is electrically neutral.
26. </span><span>Ionic compounds have high melting points and high boiling points compared to molecular compounds. Ionic compounds that are dissolved in water or melted will conduct electricity. Molecular compounds do not conduct electricity in either case.
27. </span><span>A covalent bond is formed when two atoms share valence electrons. Neither atom loses electrons or takes electrons from the other. No charged particles form. In an ionic bond, one or more electrons are transferred from one atom to another. Atoms that lose electrons become positively charged ions, and atoms that gain electrons become negatively charged ions. These oppositely charged particles then attract each other.
28. </span><span>A metal crystal consists of positively charged metal ions embedded in a "sea" of loosely held valence electrons that can move around easily. Heat travels through materials as the increased motion of the particles in the hotter parts of the material is passed along to the particles in the cooler parts. In a metal, since particles are easily set in motion, heat is easily transferred or conducted. The same is true for the conduction of electricity. Electricity can flow when charged particles, such as electrons, are free to move. Since the electrons in a metal crystal can move freely among the atoms, electricity is easily conducted.</span>
Solid Silicon can be reacted with Nitrogen gas at a high temperature to form silicon nitride (Si3N4).
1.20 moles of Silicon are added to 1.00 moles of Nitrogen gas.
(5 Points) Balance the equation and indicate the phases.
Si (___) + N2 (___) → Si3N4 (___)
(5 Points) What is the limiting reactant? You must show your work.
Balanced chemical reaction: 2CH₄(g) ⇄ C₂H₂(g) + 3H₂(g).
1) In a chemical reaction, chemical equilibrium is the state in which both reactants (methane CH₄) and products (ethyne C₂H₂ and hydrogen H₂) are present in concentrations which have no further tendency to change with time.
2) At equilibrium, both the forward and reverse reactions are still occurring.
3) Reaction rates of the forward and backward reactions are equal and there are no changes in the concentrations of the reactants and products.
Answer:
7. genetics because hereditary is not the study of hereditary.
8. is hereditary because it is the study of how things pass on to next generation what is inherited.
The monochloroderivatives will be obtained by substituting chemically non equivalent hydrogen with chlorine atom, one by one
So the possible monochloro derivatives of 2,4-dimethylpentane (figure 1) are shown in figure (2)
