Calculate the average atomic mass of element X. X-204 has an abundance of 1.4% and a mass of 203.973 amu. X-206 has an abundance of 24.1% and a mass of 205.974 amu. X-207 has an abundance of 22.1% and a mass of 206.976 amu. X-208 has an abundance of 52.4% and a mass of 207.977 amu. Can someone please help me i been stuck on this for almost a 30 minutes

How can you use chemical equations to predict the products of the reaction you can carry out?

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

What is the molarity of the solution produced when 145 g of nacl is dissolved in sufficient water to prepare 2.75 l of solution?