The question is incomplete.
You need two additional data:
1) the original volume
2) what solution you added to change the volume.
This is a molarity problem, so remember molarity definition and formula:
M = n / V in liters: number of moles per liter of solution
To give you the key to answer this kind of questions, supppose the original volumen was 1 ml and that you added only water (solvent).
The original solution was:
V= 1 ml
M = 0.2 M
Using the formula for molarity, M = n / V
n = M×V = 0.2 M × (1 / 10000)l = 0.0002 moles
For the final solution:
n = 0.0002 moles
M = 0.04
From M = n / V ⇒ V = n / M = 0.002 moles / 0.04 M = 0.05 l
Change to ml ⇒ 0.05 l × 1000 ml / l = 50 ml. This would be the answer for the hypothetical problem that I assumed for you.
I hope this gives you all the cues you need to answer similar problems about molarity.
Answer:
<em>ii</em><em> </em><em>and</em><em> </em><em>iv</em><em> </em>
Explanation:
atomic mass is the sum of protons and neutrons
protons ( postively charged) usually have the same number like electrons( negatively charged)
Answer:
the Law of multiple proportions
Explanation:
The law of multiple proportions states that, if two elements A and B combine to form more than one chemical compound, then the various masses of one of the elements A, which combines with a fixed mass of the element B are in simple multiple ratio.
This is demonstrated in the formation of nitrogen compounds such as NO and N2O when nitrogen combines with oxygen. This ratio is always constant.
<span>Avogadro's law applies at STP where P is 1 atm and T is 273K. From Avogadro's law; 1 mole of gas takes up 22.4 L of volume at STP. I. e 1 moles = 22.4 L. Hence 1.2 moles of water vapor will take up. 1.2 * 22.4 = 26.88L. Or using ideal ga s eqn PV = NRT. We have P = 1 atm. N = 1.2 moles. R = 0.0821 L and T =273 K. So V = NRT/P.Then we have 1.2 * 0.0821 * 273 = 26.88L.</span>
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
