What do triple-beam balances and stopwatches both have in common? a. they both can be used to measure mass. b. they both have buttons to start and stop measuring. c. they both need to be set to zero before taking a measurement. d. they both require you to use safety goggles when you make a measurement. answer asap 15 points

Write the complete balanced equation for the reaction between lead (iv) oxide (pbo2) and water (h2o).

The clouds are grey and ground is wet. a quantitative b qualitative

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.