Answer:
PHYSICS.
Explanation:
BLUE BOX CA BE REFERRED AS AN ELECTRONIC DEVICE WHICH IS USED IN THE TELEPHONIC CIRCIUTSTI PASS ON LONG DIATANT SIGNALS.
Answer:
pH = 11.95≈12
Explanation:
Remember the reaction among aqueous acetic acid (
) and aqueous sodium hydroxide (NaOH)

First step. Need to know how much moles of the substances are present
= 0.0025 mol NaOH
0.003 mol NaOH *
/ 1 mol NaOH = 0.003 mol CH_3COOH[/tex]
NaOH is in excess. Now, how much?
0.003 mole NaOH - 0.0025 mole NaOH = 0.0005 mole NaOH
Then, that amount in excess would be responsable for the pH.
Third step. Know the pH
Remember that pH= -log[H+]
According to the dissociation of water equilibrium
Kw=[H+]*[OH-]= 10^(-14)
The dissociation of NaOH is
NaOH -> 
Now, concentration of OH^{-}[/tex] would be given for the excess of NaOH.
[OH-]= 0.0005 mole / 0.055 L = 0.00909 M
Careful: we have to use the total volumen
Les us to calculate pH
![pH= -log [H+]\\pH= -log \frac{K_w}{[OH-]} \\pH= 11.95](https://tex.z-dn.net/?f=pH%3D%20-log%20%5BH%2B%5D%5C%5CpH%3D%20-log%20%5Cfrac%7BK_w%7D%7B%5BOH-%5D%7D%20%5C%5CpH%3D%2011.95)
Answer: 625 grams
Explanation:
14 goes into 56, 4 times.
10,000÷2=5,000 - first half life
5,000÷2=2,500 - second half life
2,500÷2=1,250 - 3rd half life
1,250÷2= 625 - 4th half life
Note: don't type "grams" after 625, just type "625".
Answer:
1.196 M NaOH
Explanation:
Molarity = moles/Volume (L)
moles NaOH = mass NaOH/MM NaOH = 12/40.01 = 0.299 moles NaOH
Volume solution = 250 mL = 0.250L
M = 0.299/0.250=1.196 M NaOH
n = PV/RT
p = 1.6 atm
v = 12.7L
R = 0.0821
T = 24°C which is equivalent to 297.15 degrees k
n = (16 × 12.7) / (0.0821 × 297.15)
n = 20.32 / 24.39
n = 0.83 mol
C = 12.90
H = 1.0079
C2 = 12.010 × 2 = 24.02
H6 = 1.0079 × 6 = 6.0474
C2H6 = 30.0674
Ethane times n which is 30.0674 × 0.83mol
= 24.95 grams of C2H6. Which is Ethane.