Answer:
The contributions are not listed in the question. I guess the following are the options you are talking about.
Same elements have same properties:
In 1803 Dalton gave the atomic theory that the properties of the atoms of the same element are same.
Electrons in Orbits:
Electrons were discovered in 1897 by J J. Thompson but the hypothesis of electrons in the orbits were given by Hantaro Nagaoka in 1904.
Plum pudding model:
Plum pudding model was given by J. J. Thompson in 1904 with the concept of positively charged medium containing the negatively charged electrons in it.
Positively Charged Atomic Nucleus:
Earnest Rutherford in 1911 discovered the positively charged atomic nucleus.
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:
electronic configuration: 1s^2,2s^2,2p^3
name: nitrogen
unpaired electron: 3
Explanation:
Answer: yellow ? i’m sorry if i’m not right
Explanation:
