About how many grams of NaCl would be dissolved in water to form a 0.5M solution in 500ml solution?
2020-08-03 11:58 pm
I used the formula for molarity in which 0.5M=x/(0.5L). I got that x is equal to 0.25mol NaCl and converted it to grams, so my final answer was 8.75g NaCl. However, the answer is 14.5g NaCl. What did I do wrong?
回答 (3)
2020-08-04 12:23 am
0.5 M = x / (0.5 L)
x = 0.25 mol NaCl
Molar mass of NaCl = (22.99 + 35.45) g/mol = 58.44 g/mol
Mass of NaCl = (0.25 mol) × (58.44 g/mol) = 14.6 g
(close to 14.5 g)
====
OR:
(0.5 mol/L NaCl) × (0.5 L) × (58.44 g NaCl / 1 mol NaCl)
= 14.6 g NaCl
(close to 14.5 g)
x = 0.25 mol NaCl
Molar mass of NaCl = (22.99 + 35.45) g/mol = 58.44 g/mol
Mass of NaCl = (0.25 mol) × (58.44 g/mol) = 14.6 g
(close to 14.5 g)
====
OR:
(0.5 mol/L NaCl) × (0.5 L) × (58.44 g NaCl / 1 mol NaCl)
= 14.6 g NaCl
(close to 14.5 g)
2020-08-04 12:05 am
0.5M NaCl has 0.050 moles NaCl / litre
so
.5L @ 0.5 moles / litre = 0.25 moles NaCl
using molar mass:
0.25 mol NaCl @ 58.44 g/mol = 1.461 g
I would dissolve 14.6 g NaCl into some water,
then add enough water to dilute it to 500 ml
so
.5L @ 0.5 moles / litre = 0.25 moles NaCl
using molar mass:
0.25 mol NaCl @ 58.44 g/mol = 1.461 g
I would dissolve 14.6 g NaCl into some water,
then add enough water to dilute it to 500 ml
2020-08-04 12:02 am
It’s 58.44 g in 1000 ml of water to make 1 M. To make .5 M, you need half so 29.22 g. But it’s only 500 ml so you need half of that, so 14.61 g.
收錄日期: 2021-04-24 08:03:20
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