Why can physical changes separate the components of a mixture but not the components of a compound?
Several types of mixtures can be separated by physical means. Heterogeneous mixtures imply the different parts are not equally distributed, much like how on a pizza the toppings are not located in the crust. A homogeneous mixture is one where the components are equally mixed, such as orange juice or lemonade (excluding the pulp).
A common heterogeneous example is to separate oil from water by placing the mixture into a separation funnel and draining one level of liquid out. You then have the two separate components. Basically, if you can see the different layers in a mixture, you can physically remove them by either picking out the solids (either with your hands or running the mixture through filter paper) or for liquids using the funnel.
b)melting ice
c)oxidation of iron
D) dissolvin ammonium nitrate in water to cool the water
Answer:
B.) Possibly making an infrence.
Explanation:
Judging on what sshe saw, she can try to infer or come up with an answer. [based on what she observed.]
B-evaporation
C-cooling
D-gravity
The answer is: the atom with more valence electrons are in the middle of a molecule and it form more bonds.
For example, molecule hydrogen cyanide (HCN).
Lewis structure for hydrogen cyanide is H:C:::N:
Hydrogen has valence one (I), it means it has one single bond and electron configuration like closest noble gas helium.
Carbon has valence four (IV), it has four bonds (one with hydrogen and three with nitrogen) and full octet.
Nitron has valence three (III), it has full octet and electron configuration like noble gas neon (Ne).
Hydrogen cyanide has linear shape (the bond angles of 180 degrees).