ANSWER:
4 a) Specific elements have more than one oxidation state, demonstrating variable valency.
For example, the following transition metals demonstrate varied valence states: 
, 
, 
, etc.
Normal metals such as 
also show variable valencies. Certain non-metals are also found to show more than one valence state 
4 b) Isotopes are members of a family of an element that all have the same number of protons but different numbers of neutrons.
For example, Carbon-14 is a naturally occurring radioactive isotope of carbon, having six protons and eight neutrons in the nucleus. However, C-14 does not last forever and there will come a time when it loses its extra neutrons and becomes Carbon-12.
5 a) 
→ 
5 b) 
→ 
5 c) 
→ 
(already balanced so don't need to change)
5 d) 
→ 
5 e) 
→ 
EXPLANATION (IF NEEDED):
1. Write out how many atoms of each element is on the left (reactant side) and right (product side) of the arrow.
2. Start multiplying each side accordingly to try to get atoms of the elements on both sides equal.
EXAMPLE OF BALANCING:
9 moles of reactants chemically change into 11 moles of product.
Explanation:
In the reaction above, 9 moles of reactants chemically change into 11 mole of products. The coefficients in a reaction is the number of moles of the reacting atoms .
- For example 8O₂ depicts 8 moles of two oxygen atoms.
- The number of moles is a unit for quantifying particles.
- You can liken it to a dozen, gross or a score.
- Since a mole of a substance contains avogadro number of particles. We can relate the number of moles to other parameters.
Learn more:
Moles brainly.com/question/2272966
#learnwithBrainly
Answer:
Explanation:
In this problem, the temperature stays constant. The volume and pressure change, so we use Boyle's Law. This states that the pressure of a gas is inversely proportional to the volume. The formula is:
Now we can substitute any known values into the formula.
Originally, the gas has a volume of 25.0 liters and a pressure of 2.05 atmospheres.
The volume is decreased to 14.5 liters, but the pressure is unknown.
Since we are solving for the new pressure, or P₂, we must isolate the variable. It is being multiplied by 14.5 liters and the inverse of multiplication is division. Divide both sides by 14.5 L .
The units of liters cancel.
The original values of volume and pressure have 3 significant figures, so our answer must have the same.
For the number we found, that is the hundredth place.
The 4 in the thousandth place (in bold above) tells us to leave the 3 in the hundredth place.
The new pressure is approximately <u>3.53 atmospheres.</u>
Answer:
A. They are nonreactive gases
Answer: option B. The kinetic energy of gas molecules is directly proportional to the Kelvin temperature of the gas.
Explanation:
The kinetic theory of gases explains the behavior and properties of gases from a molecular perspective.
Specifically and explicity, the kinetic theory of gases states that gases are constituted by particles (molecules) and that the average kinetic energy of the particles is proportional to the absolute temperature (Kelvin scale) of the gas. Furthermore, the temperature of all the (ideal) gases is the same at a given temperature.
Hence, you know that the higher the temperature of the gas, the higher the kinetic energy and the average speed of the molecules.
Other postulates of the kinetic theory of gases are that: i) the volume of the particles is neglectible; ii) the particles do not exhibit intermolecular attraction or repulsion; iii) the particles are in continuous random motion in straight paths, until they collide with other particles or the walls of the vessel, and iv) the collisions are elastic (the energy is conserved).
