A 0.400-g sample of toothpaste was boiled with a 50-mL solution containing a citrate buffer and NaCl to extract a fluoride ion. After cooling, the solution was diluted to exactly 100 mL. The potential of ISE with Ag-AgCl (sat) reference electrode in a 25.0-mL aliquote of the sample was found to be -0.1823 V. Addition of 5.0 mL of a solution containing 0.00107 mg F-/mL caused the potential to change to -0.2446 V. Calculate the percentage of F- in the sample.

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.

Ok, so i have 2 questions. try to answer them both: (the topic is fire) 1) how can you represent the chemical reaction of fire? 2) what kind of bond is formed in this chemical reaction

What is produced from neutralization of an acid and a base? a. hydronium ions b. citric acid c. salt and water