21. A chemistry teacher needed 200 mL of 1.5 M Na2 S2O3(molar mass 158 g/mole). How many grams should the teacher measure out?

Determine the number o moles of ions/atoms/particle in the following: 2.50 miles of k2s (let me know how to do)

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

George is a dalmatian puppy. describe what happens to light that allows you to see george’s black and white coat.