Which of the following chemical reactions will produce a precipitate? *
10 points
Na2CO3 + CaCl2 → CaCO3 + 2 NaCl
NH4OH + KCl → KOH + NH4Cl
ZnCl2 + Mg2SO4 → ZnSO4 + MgCl2
3 KBr + AlPO4 → K3PO4 + AlBr3

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

Which statement correctly describes metallic bonds? a. they form when certain atoms lose electrons and other atoms gain electrons. b. they involve an attraction between anions and cations. they always involvpoth a metal and a nonmetal. d. they can only form between atoms of the same element. e. they form because electrons can move freely between atoms.

Is laundry detergent an acid or a base?