This uses the concept of freezing point depression. When faced with this issue, we use the following equation:
ΔT = i·Kf·m
which translates in english to:
Change in freezing point = vant hoff factor * molal freezing point depression constant * molality of solution
Because the freezing point depression is a colligative property, it does not depend on the identity of the molecules, just the number of them.
Now, we know that molality will be constant, and Kf will be constant, so our only unknown is "i", or the van't hoff factor.
The van't hoff factor is the number of atoms that dissociate from each individual molecule. The higher the van't hoff factor, the more depressed the freezing point will be.
NaCl will dissociate into Na+ and Cl-, so it has i = 2
CaCl2 will dissociate into Ca2+ and 2 Cl-, so it has i = 3
AlBr3 will dissociate into Al3+ and 3 Br-, so it has i = 4
Therefore, AlBr3 will lower the freezing point of water the most.
Answer: B
Explanation:
There is an atom of one type of element and then two atoms of another type of element.
Answer:
The law is observed in the given equation.
Explanation:
CaCO₃ + 2HCI → CaCI₂ +H₂O + CO₂
In order to find out if the law of conservative mass is followed, we need to <u>count how many atoms of each element are there in both sides of the equation</u>:
- Ca ⇒ 1 on the left, 1 on the right.
- C ⇒ 1 on the left, 1 on the right.
- O ⇒ 3 on the left, 3 on the right.
- H ⇒ 2 on the left, 2 on the right.
- Cl ⇒ 2 on the left, 2 on the right.
As the numbers for all elements involved are the same, the law is observed in the given equation.
Answer:
Salt domes result when <u><em>the pressure of overlying rock forces the salt to rise. (Option 2)</em></u>
Explanation:
In geology it is called the gently wavy and rounded relief dome.
Salt has some special properties like rock:
- Salt has a lower specific gravity in relation to a common mineral.
- Salts deform plastically and are very mobile.
- Salts have a high water solubility.
These properties allow, if the pressure is very high, that the salt layers move upwards (due to their lower density). That is, the internal forces produce the elevation of the strata by means of the pressure they exert towards a higher point, generating that the salt looks for its way towards the surface [that is, the salt ascends through the sedimentary layers of the earth's crust, crossing them and deforming them] and causing the bulging structure. The oldest strata are located in the central area of the dome, while the most modern are distributed in the farthest radius. The structure is called salt or diapiro dome, the phenomenon by which it is formed is called diapirism.
Finally, you can say that <u><em>Salt domes result when the pressure of overlying rock forces the salt to rise.</em></u>
The correct answer is From different social and ethnic backgrounds.
Explanation:
The purpose of science studies is to gain an understanding of specific phenomena and use this in the benefit of the world or humanity. Moreover, science is guided by objective methods and these are applied all around the world. This feature allows scientists from all kinds of social and ethnic backgrounds to study the same phenomena and obtain similar results, which is essential for the progress of scientific knowledge. This is exemplified by two different labs in two different countries studying drug absorption because the results of these two studies can be analyzed together to understand drug absorption.
In this context, one factor that contributes to the progress of scientific knowledge is the effort of scientists "from different social and ethnic backgrounds".
