Let us find moles first.
Molarity = moles of solute/Liters of solution ( 750 ml = 0.750 Liters )
0.375 M Na2SO4 = moles Na2SO4/0.750 Liters
= 0.28125 moles Na2SO4
===================
0.28125 moles Na2SO4 (142.05 grams/1 mole Na2SO4)
= 39.95 grams Na2SO4 needed
---------------------------------------you do significant figures!
I must assume that this is a decomposition reaction, though you do not tell me!
Balanced equation.
Na3PO4 -> 3Na(+) + PO4(3-)
Get moles Na ions.
Molarity = moles of solute/Liters of solution (425 ml = 0.425 Liters )
0.900 M Na(+) = mole Na(+)/0.425 Liters
= 0.3825 mole Na(+)
Drive against Na3PO4
0.3825 moles Na(+) (1 mole Na3PO4/3 moles Na(+))(163.94 grams/1 mole Na3PO4)
= 20.9 grams sodium phosphate needed
Na3PO4 ==> 3Na^+ + PO4^3-
Note 1 mole Na3PO4 produces 3 moles Na^+
moles Na3PO4 needed = 0.900 mol/L x 0.525 L x 1 mol/3 mol Na = 0.1575 moles
mass Na3PO4 = 0.1575 moles Na3PO4 x 164 g/mol = 25.83 grams = 25.8 g (3 sig figs)
45.1 g/mol
40.2g
1.18g
Image result for You prepare a less concentrated H C l solution from a stock solution with 12m concentration. If you too 100g of the stock solution to prepare 4 MHCl solution how much water is needed to prepare o find solution 9density HCL(12) = 1,89/ml? The concentration would be 0.76 mol/L.
Concentration of NaOH = 0.025 M = 0.025 Moles per Litre of SolutionVolume of Solution required = 5.00LWe can say therefore that:Number of Moles of NaOH needed to prepare the solution= Concentration of NaOH * Volume of Solution requiredTherefore:Number of Moles of NaOH needed to prepare the solution= 0.025M * 5.00L= 0.125molesFrom this we can say that 0.125 moles of NaOH are needed to prepare a 5.00 L solution with a concentration of 0.025M of NaOH.
2.07g
HCl has a molar mass of 36.461 grams per mole. This means that 72.922 grams of HCl are needed per liter of water to make a solution that has a concentration of 2M.
This may be a trick question, electrolyis of a sodium chloride solution produces chlorine at the anode but does not produce sodium at the cathode. Electrolysis of molten sodium chloride does however produce sodium and chlorine.
it is solubility
Depending on the desired concentration of the solution !
5.50
Image result for You prepare a less concentrated H C l solution from a stock solution with 12m concentration. If you too 100g of the stock solution to prepare 4 MHCl solution how much water is needed to prepare o find solution 9density HCL(12) = 1,89/ml? The concentration would be 0.76 mol/L.
1.5 moles
It depends on the concentration of the solution. More info is needed to answer this question.
Concentration of NaOH = 0.025 M = 0.025 Moles per Litre of SolutionVolume of Solution required = 5.00LWe can say therefore that:Number of Moles of NaOH needed to prepare the solution= Concentration of NaOH * Volume of Solution requiredTherefore:Number of Moles of NaOH needed to prepare the solution= 0.025M * 5.00L= 0.125molesFrom this we can say that 0.125 moles of NaOH are needed to prepare a 5.00 L solution with a concentration of 0.025M of NaOH.
If it has a greater concentration, it will be considered more basic or alkaline. So, with a higher concentration, you will not need as much baking soda in your neutralization reaction.
2.07g
first measure the volume of the sample solution needed to change the blue color of the DCPIP solution into colourless. then, weigh the mass of the sample solution. finally calculate the concentration by using the formula: volume required t change the color of DCPIP solution (dm) per mass of the sample solution (g)
HCl has a molar mass of 36.461 grams per mole. This means that 72.922 grams of HCl are needed per liter of water to make a solution that has a concentration of 2M.
Sodium chloride may be used as standard (for example to prepare sodium solutions with known concentration) because is a stable compound.