In a coffee-cup calorimeter, 100.0 g of H2O and 8.70 grams of Na3PO4 are added. The water had an initial temperature of 24.6 oC. After the dissolution of the sodium phosphate the temperature changed to  31.3 oC.  -Was the dissolution exothermic or endothermic? Explain. 

-Calculate how much heat the water lost or gained.​

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

What is the independent variable in this investigation? mass volume sample number substance density

According to the valence shell electron pair repulsion (vsepr) theory, a molecule that has four electron groups around the central atom will exhibit what electron geometry? view available hint(s) according to the valence shell electron pair repulsion (vsepr) theory, a molecule that has four electron groups around the central atom will exhibit what electron geometry? trigonal bipyramidal tetrahedral square planar determination of electron geometry requires information on whether the electron groups are lone pairs or bonding groups.