A measurement is a quantitative observation involving both a number and a unit. What is a qualitative observation? What are
the SI units for mass, length, and volume? What is the assumed
uncertainty in a number (unless stated otherwise)? The uncertainty
of a measurement depends on the precision of the measuring
device. Explain.

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the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.