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>
Answer: the molarity of the solution in volumetric flask "B' is 0.0100 M
Explanation:
Given that;
the Molarity of stock solution M₁ = 1.25M
The molarity os solution in volumetric flask A (M₂) = M₂
Volume of stock solution pipet out (V₁) = 5.00mL
Volume of solution in volumetric flask A V₂ = 25.00mL
using the dilution formula
M₁V₁ = M₂V₂
M₂ = M₁V₁ / V₂
WE SUBSTITUTE
M₂ = ( 1.25 × 5.00 ) / 25.00 mL
M₂ = 0.25 M
Now volume of solution pipet out from volumetric flask A V₂ = 2.00 mL
Molarity of solution in volumetric flask B (M₃) = M₃
Volume of solution in volumetric flask B V₃ = 50.00m L
Using dilution formula again
M₂V₂ = M₃V₃
M₃ = M₂V₂ / V₃
WE SUBSTITUTE
M₃ = ( 0.25 × 2.0) / 50.0
M₃ = 0.0100 M
Therefore the molarity of the solution in volumetric flask "B' is 0.0100 M
Answer:
Increase the pressure of the gas
Explanation:
According to the Pressure law, for a fixed mass of gas, at a constant volume (V), the pressure (P) is directly proportional to the absolute temperature (T).
From the kinetic molecular theory, gases are composed of particles which are in constant motion, colliding with themselves as well as with the walls of their container.
When the temperature of these gas molecules is increased, the molecules acquire more kinetic energy and the rate of collisions increases. Since the container cannot expand, the increase in pressure is due to the increase in collisions between the molecules of the gas as well as with the walls of their container.
A, B, and C are insoluble in water
Answer:
Option A. 70.0 KPa.
Explanation:
Data obtained from the question include:
Pressure (torr) = 525.4 torr
Pressure (kPa) =?
The pressure expressed in torr can be converted kPa as shown below:
760 torr = 101.325 KPa
Therefore,
525.4 torr = (525.4 x 101.325) / 760 = 70.0 KPa.
Therefore, 525.4 torr is equivalent to 70.0 KPa.
