CHEMISTRY OXIDATION NUMBERS
please help me solve only 3 of those oxidation numbers

NO2
Cr2O72-
KCl
NH3
CaH2
SO42-
Na2O2
SiO2
CaCl2

How many moles of gas are present if p=11 atm, v=12l, t=185k?

Suppose you have designed a new thermometer called the x thermometer. on the x scale the boiling point of water is 129 ? x and the freezing point of water is 13 ? x. part a at what temperature are the readings on the fahrenheit and x thermometers the same?

Two nails have identical sizes and shapes. in one nail, 20 percent of the domains are lined up. in the other nail, 80 percent of the domains are lined up. which has stronger magnetic force? first answer gets brainliest!