Question

Which of the following contains 1.0 mol of dissolved copper(II) nitrate? 500 mL of a 0.50 mol/L solution 1.0 L of a 0.9 mol/L solution O 750 mL of 0.75 mol/L solution 500 mL of 2.0 mol/L solution

Answer 1

The solution of aqueous acetic acid that is supplied to schools has a concentration of 14 mol/L. Your class needs 3.0 L of a solution with a concentration of 0.10 mol/L. What volume of the stock solution is needed to prepare 3.0L of 0.10 mol/L CH3COOH(aq)?

Answer 2

Helpppppppppp

Answer 3

First question: multiply volume * molarity to get moles (notice how L * Moles/L gives you moles when you cancel out units).

Starting with the first answer choice: 500 mL of a 0.50 mol/L solution —> 0.5 L * 0.5 mol/L = 0.25 moles so this isn’t it. Repeat with the rest of the choices until you get 1.0 moles

Answer 4

Second question: M1V1 = M2V2

Where M1 V1 are the molarity and volume of the stock, and M2 V2 are the molarity of the prepared solution

It’s asking for how much stock you need, so you can plug in M1, M2 and V2 and solve for V1

Answer 5

Lead(II) sulfide, PbS(s), is an insoluble substance. Calculate the maximum mass of lead(II) sulfide that will precipitate when 6.75 g of sodium sulfide, Na2S(s), is added to 250 mL of 0.200 mol/L lead(II) nitrate, Pb(NO3)2(aq).

Answer 6

The concentration of ammonium carbonate, (NH4)2CO3 (s) when dissolved in water
was found to be 5.70 mol/L. What is the concentration of ammonium ions in this 1.00L
solution, expressed in mol/L?

Answer 7

For the lead sulfide question you need to write the balanced equation between sodium sulfide and lead nitrate, calculate the limiting reactant between those two, and determine how much lead sulfide you get from that

Answer 8

For the ammonium one, since each ammonium carbonate molecule has 2 ammonium ions, you can simply multiply the concentration of ammonium carbonate * 2