Answer:
Sound waves and light waves need to change places
Explanation:
Just did this assignment on edge. Sound waves are mechanical because they need matter to travel through, while light waves are electromagnetic.
They are activating which is causing them to do this
Question: What is the molality of a solution prepared by dissolving 86.9 g of diethyl ether, C4H10O, in 425 g of benzene, C6H6?
Answer: 2.76 mol/kg
Explanation:
Formula of morality is moles of solute divided by the mass of the solvent.
Molality = moles of solute/ mass of solvents (kg)
Mass of solvent is 425g = 0.452kg
Moles = mass / molar mass
Mass of diethyl ester = 86.9g
Molar mass of diethyl ether (C4H10O) = 12*4 + 1*10+ 16
= 48+ 10 + 16
= 74g/mol.
So moles of diethyl ester = 86.9 g / 74 g/mol= 1.17 mol
molality = 1.17mol/0.425kg = 2. 75 mol/kg
Answer is 2. 76 mol approximately.