Answer:
Explanation:
To convert atoms to moles, Avogadro's Number must be used: 6.022*10²³.
This tells us the amount of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case it is the atoms of potassium. We can create a ratio.
Multiply by the given number of moles: 15.2
The moles of potassium cancel.
The denominator of 1 can be ignored.
Multiply.
The original measurement of moles has 3 significant figures, so our answer must have the same. For the number we calculated that is the hundredth place. The 3 in the thousandth place tells us to leave 5.
In 15.2 moles of potassium, there are <u>9.15*10²⁴ atoms of potassium.</u>
If the conjugate base of a molecule has a pKb of 1.4, the molecule should be a Weak Acid.
Notice this question gives us the pKb of the molecule, not the pKa. Because of this, the pH scale basically gets reversed, so lower numbers in pKb correlate with stronger bases, and higher numbers in pKb correlate with stronger acids - the exact opposite of the pH scale.
It's important to make sure you completely understand the terms of conjugate base, conjugate acid, pKb, pKa, and how they all relate. It's easy to mix up the meanings of these definitions.
Here are the two other pieces of information you need to know to correctly answer this question:
- Strong acids have a weak conjugate base.
- Strong bases have a weak conjugate acid.
So if the problem says you have a strong conjugate base, then the molecule must be a weak acid. To illustrate this, think of ammonium, NH4+. Ammonium is a weak acid, but the conjugate base of ammonium is ammonia, NH3, which is a reasonably good base.
Learn more about conjugate base here : brainly.com/question/22514615
#SPJ4
A molecular size affects the rate of evaporation when the larger the intermolecular forces in a compound, the slower the evaporation rate and this correlates with temperature change.
Molecular size seems to have an effect on evaporation rates in that the larger a molecule gets or grows from a base chemical formula, its evaporation rate will get slower.
<h3>What is the molecular size?</h3>
This is a measure of the area a molecule occupies in three-dimensional space as this relates to the physical size of an individual molecule.
Hence, we can see that a molecular size affects the rate of evaporation the larger the forces, the lower the rate.
Read more about<em> molecular size</em> here:
brainly.com/question/16616599
#SPJ1
Answer:
The plum-pudding model did not identify a central nucleus as the source of a positive charge.
Explanation:
Sir Joseph John Thomson, most popularly known as J J Thomson. He was a famous scientist who was awarded the Noble prize for Physics for his discovery of the subatomic particle, electron.
He placed his famous model of an atom which is known as plum pudding model. He proposed that the atoms are described as the negative particles that is floating within a soup of the diffuse positive charge.
But the main defect of his proposal was that it did not recognized the presence of a central nucleus as a positive charged source.
A. Smell (Oder) B. Color and D I’m pretty sure because the common properties are Color, Oder, Melting point, and boiling point
