how many grans of Ca(OH) are needed to prepare 800.0 ml solution of 0.15M concentration? molar mass of Ca(OH) is 74g/mole

Hi faye,

Alright so we want to prepare a 800ml solution of 0.15M concentration.

So first we calculate the amount of Ca(OH)2 **NOTE: SHOULD NOT BE CA(OH) COS +2 CHARGE OF CA2+ IS NOT BALANCED! CA(OH)2 IS A SOLID AND NOT AN ION, HENCE THE COMPOUND CANNOT HAVE AN OVERALL CHARGE. **

Amount (mol) of Ca(OH)2 = M (mol/dm^3) X L (dm^3) = 0.15 X 800.0/1000 (must convert to appropriate units)

Then mass (g) = molar mass (g/mol) X amount (mol) giving you your mass of Ca(OH)2 needed.

Hope I helped! (:
-J

Oops, sorry, my apologies for typing in caps. Was just trying to point that out. :)

...and the answer should only be to 2 sig figs.

To determine the number of grams of Ca(OH)2 needed to prepare the solution, we'll use the formula:

Grams of solute = (Molarity) x (Volume in liters) x (Molar mass)

First, let's convert the volume from milliliters to liters:

Volume = 800.0 ml / 1000 = 0.8 L

Now, we can calculate the grams of Ca(OH)2:

Grams of Ca(OH)2 = (0.15 M) x (0.8 L) x (74 g/mol)

Multiplying these values, we get:

Grams of Ca(OH)2 = 8.88 g

Therefore, you would need 8.88 grams of Ca(OH)2 to prepare an 800.0 ml solution with a molar concentration of 0.15 M.