Answer:
Record players
Explanation:
In a record player, a stylus vibrates as it follows a spiral groove cut into the surface of the rotating record.
The vibrations (analogue) are converted into electrical signals and fed into an amplifier to produce the sounds you hear
Fiber optic cables, Wi-Fi devices, and flat screen TVs use digitized signals to encode and transmit information
The basic units for density is
and any get of units that has those units in the proper place can be considered a density unit. The ones that has those specifically are A, B, E and F
Answer:
Explanation:
In weight/volume (w/v) terms,
1 ppm = 1g m-3 = 1 mg L-1 = 1 μg mL-1
200 mL = 0.2 L
15 / 0.2 mg L-1 =75 ppm
To fully understand the problem, we use the ICE table to identify the concentration of the species. We calculate as follows:
Ka = 2.0 x 10^-9 = [H+][OBr-] / [HOBr]
HOBr = 0.50 M
KOBr = 0.30 M = OBr-
<span> HOBr + H2O <-> H+ + OBr- </span>
<span>I 0.50 - 0 0.30 </span>
<span>C -x x x
</span>---------------------------------------------
<span>E(0.50-x) x (0.30+x) </span>
<span>Assuming that the value of x is small as compared to 0.30 and 0.50 </span>
<span>Ka = 2.0 x 10^-9 = x (0.30) / 0.50) </span>
<span>x = 3.33 x 10^-9 = H+</span>
pH = 8.48
The molarity of NaOH needed is calculated as follows
calculate the moles of KhC8h4O4
that is moles = mass/molar mass of KhC8h4O4(204.22 g/mol)
=0.5632g /204.22g/mol= 2.76 x10^-3 moles
write the equation for reaction
khc8h4O4 + NaOH ---> KNaC8h4O4 + H2O
from the equation above the reacting ratio of KhC8h4O4 to NaOh is 1:1 therefore the moles of Naoh is also 2.76 x10^-3 moles
molarity of NaOh = (moles of NaOh / volume ) x 1000
that is { (2.76 x10^-3) / 23.64} x100 =0.117 M
