You must determine the concentration first of the concentrated HCl, typically concentrated HCl is a 36-38% HCL which works out to about 12-12.2 N concentration. From there all you have to due is...
You must take 88,8 mL concentrated HCL and fill up to 1000 mL with distilated water. (REMEMBER: ALWAYS ADD ACID TO WATER! - add 88.8mL to 900mL water and dilute to final volume = 1L)
The simplest...
M is for moles/L. So, you all you would need to do is add 2 times the amount in L of water to the solid HCl. For example, if you have 3 moles of solid HCl, add 6 L and you will have .5M HCl.
Take 10 mls. of 1M HCl and add distilled water till total volume becomes 100mls. now it is 0.1M HCl.
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