The parameter pH is a measure of the substance's acidity or basicity. It is quantitatively equal to the negative logarithm of the concentration of H+ ions. So, the lower the pH, the more acidic the substance, Otherwise, the higher the pH the more basic the substance. The pH range runs from 1 to 14, with 7 being neutral.
So, if we are asked to distinguish which of those have the lowest pH, we have to know the moles of H+ ions. Since all of them have a concentration of 0.1 M, concentration is not a factor. Thus, we just have to identify the strongest acid among the list. That is easy to answer because you only have to remember 7 strong acid occurring in nature: HCl, H₂SO₄, HNO₃, HClO₄, HClO₃, HBr, and HI. Since only HNO₃ is included in the list among the choices, the answer would be letter D.
The formula is Al2O<span>3. 2 aluminium and 3 oxygen
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Answer:
VSEPR theory
Explanation:
The valence shell electron pair repulsion theory was propounded by Gillespie and Nylom (1957).
The entire idea of the VSEPR theory is that the shape of a molecule depends on the electrostatic repulsion between electron pairs surrounding the central atom in a molecule which causes these pairs to be separated as far as possible.
The shapes of many molecules can be accurately predicted based on this model.
Initial pressure of the gas = 65.3 kPa
Initial volume of the gas = 654 cm³
Initial temperature of the gas = 6⁰C = 273 + 6 = 279 K
Final pressure of the gas = 108.7 kPa
Final temperature of the gas = 4⁰C = 273 + 4 = 277 K
Using the combined gas law for ideal gases:
P₁V₁/T₁ = P₂V₂/T₂
where P₁, V₁ and T₁ are the pressure, volume and temperature for the initial state and P₂, V₂ and T₂ are the pressure, volume and temperature for the final state.
Plugging the given data into the combined gas law we have,
(65.3 kPa x 654 cm³) / (279 K) = (108.7 kPa x V₂)/(277 K)
V₂ = (65.3 kPa x 654 cm³ x 277 K) / (279 K x 108.7 kPa)
V₂ = 390.1 cm³
