If 30cm³ of 0.45 mol dm3 HCl reacted with NaOH, how many moles of HCl reacted?

Moles HCl reacted : 0.0135

Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution

Where

M = Molarity

n = Number of moles of solute

V = Volume of solution

So to find the number of moles can be expressed as

n = V x M

The volume of HCl 30 cm³=3.10⁻² dm³

Molarity of HCl = 0.45 mol/dm³

so moles HCl reacted :

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

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