Explanation:
Some Rules Regarding Oxidation Numbers:
- Hydrogen has oxidation number of + 1 except in hydrides where it is -1
- Oxygen has oxidation number of -2 except in peroxides where it is -1
- Some elements have fixed oxidation numbers. E.g Halogen group elements has oxidation number of -1
- Oxidation number of a compound is the sum total of the individual elements and a neutral compound has oxidation number of 0.
A. HI
Hydrogen has oxidation of + 1
Oxidation number of I:
1 + x = 0
x = -1
B. PBr3
Br has oxidation number of - 1
Oxidation number of Pb:
x + 3 (-1) = 0
x = + 3
C. KH
Hydrogen has oxidation of + 1
Oxidation number of K:
1 + x = 0
x = -1
D. H3PO4
Hydrogen has oxidation number of + 1
Oxygen has oxidation number of -2
Oxidation number of P:
3(1) + x + 4(-2) = 0
3 + x - 8 =0
x = 5
Answer:
A. A scientist investigates a mouse's growth in nature by watching the animal.
A field study is a raw collection of data, typically in the natural habit of the organism; hence why an experiment taken in a lab isn't a field study.
Cause latin name of Pb is plumbum.
The same K - potassium - latin name is kalium.
Valence electrons are found AT THE OUTERMOST SHELL OF AN ATOM.
Valence electron refers to those electrons that are located furthest away from the nucleus of an atom, that is, they are found at the outermost shell. Valence electrons determine the chemical properties of an element and they are the only ones that get involved in chemical reactions with other elements.