I think the best answer from the given choices is option D. <span>Salt water is made up of more than one pure substance. It consists of salt and water. When each component exist alone in a container they are considered as pure substance however when mixed they are now a solution.</span>
the mass of ice taken = 10 g
the mass of water = 250 g
initial temperature of water = 20 C
the final temperature of water = 16. 8 C
specific heat of water = 4.18 J/g*K
the heat absorbed by ice to melt = heat loss by water
heat loss by water = mass X specific heat of water X change in temperature
heat loss by water = 250 X 4.18 X (20-16.8) = 3344 Joules
heat gained by ice = 3344 J
heat gained by ice = enthalpy of fusion X moles of ice
moles of ice = mass / molar mass = 10 / 18 = 0.56 moles
enthalpy of fusion = 3344 / 0.56 = 5971.43 J / mole
Answer:
pH = 4.543
Explanation:
- CH3CH2COOH + H2O ↔ CH3CH2COO- + H3O+
- pKa = - Log Ka
∴ Ka = [H3O+][CH3CH2COO-]/[CH3CH2COOH]
∴ pKa = 4.87
⇒ Ka = 1.349 E-5 = [H3O+][CH3CH2COO-]/[CH3CH2COOH]
added 300 mL 0f 0.02 M NaOH:
⇒ <em>C</em> CH3CH2COOH = ((0.200 L)(0.15 M)) - ((0.300 L)(0.02 M))/(0.3 + 0.2)
⇒ <em>C</em> CH3CH2COOH = 0.048 M
⇒ <em>C</em> NaOH = (0.300 L)(0.02 M) / (0.3 +0.2) = 0.012 M
mass balance:
⇒ 0.048 + 0.012 = 0.06 M = [CH3CH2COO-] + [CH3CH2COOH].......(1)
charge balance:
⇒ [H3O+] + [Na+] = [CH3CH2COO-]
∴ [Na+] = 0.02 M
⇒ [CH3CH2COO-] = [H3O+] + 0.02 M.............(2)
(2) in (1):
⇒ [CH3CH2COOH] = 0.06 M - 0.02 M - [H3O+] = 0.04 M - [H3O+]
replacing in Ka:
⇒ 1.349 E-5 = [H3O+][([H3O+] + 0.02) / (0.04 - [H3O+])
⇒ (1.349 E-5)(0.04 - [H3O+]) = [H3O+]² + 0.02[H3O+]
⇒ 5.396 E-7 - 1.349 E-5[H3O+] = [H3O+]² + 0.02[H3O+]
⇒ [H3O+]² + 0.02001[H3O+] - 5.396 E-7 = 0
⇒ [H3O+ ] = 2.867 E-5 M
∴ pH = - Log [H3O+]
⇒ pH = 4.543
The correct answer of the given question above would be FLAGELLA. The structure that makes it possible for some kinds of prokaryotic cells to move around is the FLAGELLA. Prokaryotic cell is one of the types of cells. The other type is the Eukaryotic cell. This cell is found in two Kingdoms of life which are Archaea and Bacteria. Hope this answer helps.
