H2O became a vapor when heated because thats the only one that can go back to its normal state, which is what a physical change is.
Hey there!
Na + H₂O → NaOH + H₂
First, balance O.
One on the left, one on the right. Already balanced.
Next, balance H.
Two on the left, three on the right. Let's add a coefficient of 2 in front of NaOH and a coefficient of 2 in front of H₂O, so we have 4 on each side.
Na + 2H₂O → 2NaOH + H₂
Lastly, balance Na.
One on the left, two on the right. Add a coefficient of 2 in front of Na.
2Na + 2H₂O → 2NaOH + H₂
This is our final balanced equation.
Hope this helps!
Molarity= (number of moles of that substance) / (Volume of solution in litres)
7= (number of moles of HCl) / 0.05
Thus,
Number of moles of HCl = 7 x 0.05 = 0.35
The number of moles of HCl will remain unchanged.
Now, for new solution,
0.35= 0.35 / (New volume of solution in litres)
Thus,
New volume = 1 litre
Thus, amount of water added = 1- 0.05 litre = 5.0 M
