Answer:
The answer is C (or 3 in this case)
Explanation:
I took the test and got it correct and the explanation is that the watershed will flow into more water which spreads that pollution and as it flows could pick up more pollution.
Answer:
3.25 moles of H2O
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
2HCl + Ca(OH)2 —> CaCl2 +2H2O
Now, we can obtain the number of mole H2O produced from the reaction as follow:
From the balanced equation above,
2 moles of HCl reacted to produce 2 moles of H2O.
Therefore, 3.25 moles of HCl will also react to produce 3.25 moles of H2O.
Therefore, 3.25 moles of H2O were produced from the reaction.
First, we should get moles acetic acid = molarity * volume
=0.3 M * 0.5 L
= 0.15 mol
then, we should get moles acetate = molarity * volume
= 0.2 M * 0.5L
= 0.1 mol
then, we have to get moles of OH- which added:
moles OH- = molarity * volume
= 1 M * 0.02L
= 0.02 mol
when the reaction equation is:
CH3COOH + OH- → CH3COO- + H2O
moles acetic acid after adding OH- = (0.15-0.02)
= 0.13M
moles acetate after adding OH- = (0.1 + 0.02)
= 0.12 M
Total volume = 0.5 L + 0.02 L= 0.52 L
∴[acetic acid] = moles acetic acid after adding OH- / total volume
= 0.13mol / 0.52L
= 0.25 M
and [acetate ) = 0.12 mol / 0.52L
= 0.23 M
by using H-H equation we can get PH:
PH = Pka + ㏒[salt/acid]
when we have Ka = 1.8 x 10^-5
∴Pka = -㏒Ka
= -㏒ 1.8 x 10^-5
= 4.7
So by substitution:
∴ PH = 4.7 + ㏒[acetate/acetic acid]
= 4.7 + ㏒(0.23/0.25)
= 4.66
Answer: Physical change
Explanation: Condensation is the phase change of a gas to the liquid state. There is no formation of new products so it does not undergoes chemical change. Any phase change is considered a physical change.
Answer: It is a basic solution with pH =8.51
Explanation:
We were given that hydroxide ion concentration [OH-] as 3.26 x 10-6 M
But We know thar
[OH-] [H+] = 1 × 10^-14
To get the Hydrogen ion [H+] concentration, we have that
[H+] = 1 × 10^-14 M/[OH-]
= 1 × 10^-14 M/3.26 x 10-6 M
= 3.067 x 10^-9 M
But, pH = - log [H+]
Therefore,
pH = - log (3.067 x 10^-9)
pH=8.51
when pH > 7, The solution is basic, therefore a solution with pH =8.51 is basic.