Answer:
The correct answer is d.hydrogen peroxide H₂O₂H₂O₂
Explanation:
Substances can be found in nature in different <em>aggregation states. </em>
Agreggation states can be liquid, gas or solid.
The problem asks about which substance can be found in room temperature as <em>liquid.</em> Each subtances has different physical and chemical properties that determines in which state you can find them at room temperature.
Hydrogen peroxide is the only substance listed that is in liquid state at room temperature, all other substances are in gas state at room temperature.
In the early 1900s, a scientist named Alfred Wegener noticed how the continents seem to fit together and developed the Theory of Continental Drift. Continental drift is the theory that continents can drift apart from one other and have done so in the past. Wegner's theory also explained why fossils of the same plant and animal species are found on both sides of the Atlantic Ocean. In addition similar types of rock and evidence of the same ancient climatic conditions are found on several continents.
Wegner hypothesized that all the separate continents of today were once joined in a single landmass that he called Pangaea.
Answer:
Explanation:
To calculate pH you need to use Henderson-Hasselbalch formula:
pH = pka + log₁₀ ![\frac{[A^-]}{[HA]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BA%5E-%5D%7D%7B%5BHA%5D%7D)
Where HA is the acid concentration and A⁻ is the conjugate base concentration.
The equilibrium of acetic acid is:
CH₃COOH ⇄ CH₃COO⁻ + H⁺ pka: 4,75
Where <em>CH₃COOH </em>is the acid and <em>CH₃COO⁻ </em>is the conjugate base.
Thus, Henderson-Hasselbalch formula for acetic acid equilibrium is:
pH = 4,75 + log₁₀ ![\frac{[CH_{3}COO^-]}{[CH_{3}COOH]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BCH_%7B3%7DCOO%5E-%5D%7D%7B%5BCH_%7B3%7DCOOH%5D%7D)
a) The pH is:
pH = 4,75 + log₁₀ ![\frac{[2 mol]}{[2 mol]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B2%20mol%5D%7D%7B%5B2%20mol%5D%7D)
<em>pH = 4,75</em>
<em></em>
b) The pH is:
pH = 4,75 + log₁₀ ![\frac{[2 mol]}{[1mol]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B2%20mol%5D%7D%7B%5B1mol%5D%7D)
<em>pH = 5,05</em>
<em></em>
I hope it helps!
The heat of solution is -51.8 kJ/mol
<h3>What is the heat of solution?</h3>
We know that in a calorimeter, there is no loss or gain of energy. It is a good example of a closed system.
Number of moles of KOH = 11.9-g/56 g/mol = 0.21 moles
Temperature rise = 26.0 ∘c
Mass of the water = 100.0 grams
Heat capacity = 4.184 j/g⋅°c
Then;
ΔH = mcθ
ΔH = 100g * 4.184 j/g⋅°c * 26.0 ∘c = 10.88 kJ
Heat of solution = -(10.88 kJ/ 0.21 moles) = -51.8 kJ/mol
Learn more about heat of solution:brainly.com/question/24243878
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To determine the name of an anion, you take the name of its element and replace the end with "ide".
<h3>What is an anion?</h3>
An anion in chemistry is a negatively charged ion.
Anions are usually formed when a non-metallic atom gains electron(s).
An anion is usually named by taking the elemental name, removing the ending, and adding “ide.
Examples of anions are as follows:
- fluoride (F-)
- Chloride (Cl-)
- Iodide (I-)
Learn more about anions at: brainly.com/question/15578817
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