Answer:
False
Explanation: sound travels fastest through solids slowest through liquids.
Answer:
0.4 M
Explanation:
Molarity is defined as moles of solute, which in your case is sodium hydroxide,
NaOH
, divided by liters of solution.
molarity
=
moles of solute
liters of solution
Notice that the problem provides you with the volume of the solution, but that the volume is expressed in milliliters,
mL
.
Moreover, you don't have the number of moles of sodium hydroxide, you just have the mass in grams. So, your strategy here will be to
determine how many moles of sodium hydroxide you have in that many grams
convert the volume of the solution from milliliters to liters
So, to get the number of moles of solute, use sodium hydroxide's molar mass, which tells you what the mass of one mole of sodium hydroxide is.
7
g
⋅
1 mole NaOH
40.0
g
=
0.175 moles NaOH
The volume of the solution in liters will be
500
mL
⋅
1 L
1000
mL
=
0.5 L
Therefore, the molarity of the solution will be
c
=
n
V
c
=
0.175 moles
0.5 L
=
0.35 M
Rounded to one sig fig, the answer will be
c
=
0.4 M
Explanation:
Answer:- The Ka for the acid is 
.
Solution:- In general, monoprotic acid could be represented by HA. The dissociation equation for the ionization of HA is written as:
HA(aq)\rightarrow H^+(aq) + A^-(aq)
Now, we make the ice table for this equation as:
HA(aq)\rightarrow H^+(aq) + A^-(aq)
I 0.25 0 0
C -X +X +X
E (0.25 - X) X X
where, I stands for initial concentration, C stands for change in concentration and E stands for equilibrium concentration.
X is the change in concentration and from ice table it's same as the concentration of hydrogen ion that is calculated from given pH.
![Ka = [H^+][A^-]\frac{1}{HA}](https://tex.z-dn.net/?f=Ka%20%3D%20%5BH%5E%2B%5D%5BA%5E-%5D%5Cfrac%7B1%7D%7BHA%7D)
Where, Ka is the acid ionization constant. Let's plug in the values.
Let's calculate the value of X first using the equation:
![pH = -log[H^+]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH%5E%2B%5D)
[/tex]
on taking antilog ob above equation we get:
![[H^+]=10^-^p^H](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E-%5Ep%5EH)
![[H^+]=10^-^2^.^7^1](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D10%5E-%5E2%5E.%5E7%5E1)
![[H^+]](https://tex.z-dn.net/?f=%5BH%5E%2B%5D)
= 0.00195
So, X = 0.001195
Let's plug in this value of X in the equation:-
So, the value of Ka for butyric acid is .
Answer:
The Kc is 1.36 (but this is not an option, may be the options are wrong, or may be I was .. Thanks!)
Explanation:
Let's think all the situation.
2 ICl(g) ⇄ I₂(g) + Cl₂(g)
Initially 0.20 - -
Initially I have only 0.20 moles of reactant, and nothing of products. In the reaction, an x amount of compound has reacted.
React x x/2 x/2
Because the ratio is 2:1, in the reaction I have the half of moles.
So in equilibrium I will have
(0.20 - x) x/2 x/2
Notice that I have the concentration in equilibrium so:
0.20 - x = 0.060
x = 0.14
So in equilibrium I have formed 0.14/2 moles of I₂ and H₂ (0.07 moles)
Finally, we have to make, the expression for Kc and remember that must to be with concentration in M (mol/L).
As we have a volume of 2L, the values must be /2
Kc = ([I₂]/2 . [H₂]/2) / ([ICl]/2)²
Kc = (0.07/2 . 0.07/2) / (0.060/2)²
Kc = 1.225x10⁻³ / 9x10⁻⁴
Kc = 1.36
