Question

how many grams of $c_2h_5oh$ are there in 2.58 mol?
25g of nacl = ______ mol cl(10 points)

Explanation:

Step1: Calculate molar mass of NaCl

Molar mass of Na: $22.99\ g/mol$, molar mass of Cl: $35.45\ g/mol$.
Molar mass of NaCl = $22.99 + 35.45 = 58.44\ g/mol$.

Step2: Find moles of NaCl

Moles of NaCl = $\frac{mass}{molar\ mass} = \frac{25\ g}{58.44\ g/mol} \approx 0.4278\ mol$.

Step3: Relate moles of NaCl to moles of Cl

In $NaCl$, 1 mole of $NaCl$ contains 1 mole of $Cl^-$. So moles of Cl = moles of NaCl $\approx 0.428\ mol$.

Answer:

$\approx 0.428$