A government laboratory wants to determine whether water in a certain city has any traces of fluoride and whether the concentration exceeds the recommended 4.00 ppm. A 5.00-g sample of this water is found to have 0.152 mg of fluoride. Should the water be declared safe for drinking?

Acrystal that absorvd water from air is (blank)a. aqueousb. homogenousc. hygroscopicd. efflorescent

Diffraction is when light is bent around obstructions. which of the these observation about clouds would indicate diffraction? a) after rain storms, you can sometimes see rainbows. b) clouds are white or gray and cannot be seen through. c) on a cloudy day, the temperature tends to be cooler than a sunny day. d) the edges of dark clouds appear lighter. this

An atom with 7 protons, 6 neutrons, and 7 electrons has an atomic mass of amu. (enter a whole number.) numerical answers expected! answer for blank 1: