Which of these mixtures are heterogeneous? 1.brass (an alloy of copper and zinc) 2.granite (a type of rock with multicolor spots) 3.oil and water 4.salt and water

How much energy is made when a pice of wood burns. how do you know

8) a mixture of he, ne and ar has a pressure of 7.85 atm. if the ne has a mole fraction of 0.47 and 8) ar has a mole fraction of 0.23, what is the pressure of he? a) 4.2 atm b) 3.7 atm c) 5.5 atm d) 2.4 atm e) 1.8 atm

Hey guys so i need to know what is _nh3+> nh4oh ~chemistry~