Friction occurs when two surfaces come into contact. Excess friction hinders movement, and it wastes energy. Friction refers to a force that opposes motion. It is important because it is applied in almost all life processes.
Answer:
Both b and d can be correct
Explanation:
Generally, diffusion does not require energy (<em>making option a wrong</em>) because it is the movement of particles from a region of high concentration to a region of low concentration hence diffusion moves particles in the direction of a concentration gradient. An example of this is the passive transport (for instance, uptake of glucose by a liver cell).
However, in some cases, when diffusion is against the concentration gradient (i.e when particles move from a region of low concentration to a region of high concentration), diffusion will require energy in a case like this (<em>making option c wrong</em>). An example of this is active transport (transport of protein called sodium-potassium pump which involves pumping of potassium into the cell and sodium out of the cell).
The explanation above shows that diffusion can require energy to move particles (in or out) of the cell through the cell membrane.
The mass of Ba(IO3)2 that can be dissolved in 500 ml of water at 25 degrees celcius is 2.82 g
<h3>What mass of Ba(IO3)2 can be dissolved in 500 ml of water at 25 degrees celcius?</h3>
The Ksp of Ba(IO3)2 = 1.57 × 10^-9
Molar mass of Ba(IO3)2 = 487 g/mol?
Dissociation of Ba(IO3)2 produces 3 moles of ions as follows:
![Ksp = [Ba^{2+}]*[IO_{3}^{-}]^{2}](https://tex.z-dn.net/?f=Ksp%20%3D%20%5BBa%5E%7B2%2B%7D%5D%2A%5BIO_%7B3%7D%5E%7B-%7D%5D%5E%7B2%7D)
![[Ba(IO_{3})_{2}] = \sqrt[3]{ksp} =\sqrt[3]{1.57 \times {10}^{ - 9} } \\ [Ba(IO_{3})_{2}] = 1.16 \times {10}^{-3} moldm^{-3}](https://tex.z-dn.net/?f=%5BBa%28IO_%7B3%7D%29_%7B2%7D%5D%20%3D%20%20%5Csqrt%5B3%5D%7Bksp%7D%20%3D%3C%2Fp%3E%3Cp%3E%5Csqrt%5B3%5D%7B1.57%20%5Ctimes%20%20%7B10%7D%5E%7B%20-%209%7D%20%7D%20%5C%5C%20%20%5BBa%28IO_%7B3%7D%29_%7B2%7D%5D%20%3D%201.16%20%5Ctimes%20%20%7B10%7D%5E%7B-3%7D%20moldm%5E%7B-3%7D)
moles of Ba(IO3)2 = 1.16 × 10^-3 × 0.5 = 0.58 × 10^-3 moles
mass of Ba(IO3)2 = 0.58 × 10^-3 moles × 487 = 2.82 g
Therefore, mass Ba(IO3)2 that can be dissolved in 500 ml of water at 25 degrees celcius is 2.82 g.
Learn more about mass and moles at: brainly.com/question/15374113
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Answer:
5 × 10^-4 L
Explanation:
The equation of the reaction is;
2KClO3 = 2KCl + 3O2
Number of moles of KClO3 = 13.5g/122.5 g / mol = 0.11 moles
From the stoichiometry of the reaction;
2 moles of KClO3 yields 3 moles of O2
0.11 moles of KClO3 yields 0.11 × 3/2 = 0.165 moles of oxygen gas
From the ideal gas equation;
PV= nRT
P= 85.4 × 10^4 KPa
V=?
n= 0.165
R= 8.314 J K-1 mol-1
T= 40+273 = 313K
V= 0.165 ×8.134 × 313/85.4 × 10^4
V=429.4/85.4 × 10^4
V= 5 × 10^-4 L
Answer: Im thinking the answer Is B) Bar graph?
Explanation:
