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: -
24 grams per kilogram.
Explanation: -
We know that
The mixing ratio = actual (measured) mass of water vapor (in parcel) in grams / mass of dry (non water vapor) air (in parcel) in kilogram
The saturation mixing ratio = mass of water vapor required for saturation (in parcel) in grams/ mass of dry (non water vapor) air (in parcel) in kilograms
Relative humidity = actual (measured) water vapor content/ maximum possible water vapor amount (saturation)
Thus saturation mixing ratio = Mixing ratio / relative humidity
= 6 / (25/100)
= 24
Add the change in temperature to your substance's original temperature to find its final heat. For example, if your water was initially at 24 degrees Celsius, its final temperature would be: 24 + 6, or 30 degrees Celsius.
Actually, there are four kinds of reptile motion:
Concertina - vermiform. Circular muscles around the snake squeeze the front of the snake's body out long, then the latter half is pulled forward.
Rectilinear crawling - Belly scutes are moved forward individually in a wave-like motion.
Side-winding - Snake's version of "walking". Use by several species to move over fluidic substrates, such as sand.
Lateral undulation - Most common form of movement. Snake presses on alternating pressure points to force body forward (or backward)
(taken from a user on Yahoo from Correct Answers)
