A burning splint will burn more vigorously in pure oxygen than in air because <span>oxygen is a reactant in combustion and concentration of oxygen is higher in pure oxygen than is in air.
Oxygen concentration in air is approximately 20%, the rest of are nitrogen, carbon dioxide and other gases. Oxygen is oxidazing reactant, that means oxygen give electrons in chemical reactions.
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The concentration of the hydronium ion in hydrochloric acid is 0.0045 M, and the pH of the solution is 2.34.
<h3>What is pH?</h3>
pH is the potential of the hydrogen or the hydronium ions in the aqueous solution.
As the solution contains 
HCl the concentration of the hydronium ion will be the same, 
The pH of the solution is calculated as:
![\begin{aligned} \rm pH &= \rm -log[H^{+}]\\\\&= - \rm log (4.5 \times 10^{-3})\\\\&= 2.34\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%5Crm%20pH%20%26%3D%20%5Crm%20-log%5BH%5E%7B%2B%7D%5D%5C%5C%5C%5C%26%3D%20-%20%5Crm%20log%20%284.5%20%5Ctimes%2010%5E%7B-3%7D%29%5C%5C%5C%5C%26%3D%202.34%5Cend%7Baligned%7D)
The concentration of the hydroxide ion is calculated from pH and hydronium ion as:
![\begin{aligned} \rm [H_{3}O^{+}][OH^{-}] &= 10^{-14}\\\\&= \dfrac{1 \times 10^{-14}}{4.5 \times 10^{-3}}\\\\&= 2.2 \times 10^{12}\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%5Crm%20%5BH_%7B3%7DO%5E%7B%2B%7D%5D%5BOH%5E%7B-%7D%5D%20%26%3D%2010%5E%7B-14%7D%5C%5C%5C%5C%26%3D%20%5Cdfrac%7B1%20%5Ctimes%2010%5E%7B-14%7D%7D%7B4.5%20%5Ctimes%2010%5E%7B-3%7D%7D%5C%5C%5C%5C%26%3D%202.2%20%5Ctimes%2010%5E%7B12%7D%5Cend%7Baligned%7D)
Now, for the calcium hydroxide solution, the calculations are shown as,
pOH is calculated as:
![\begin{aligned} \rm pOH &= 14- 8 = 6\\\\\rm [OH^{-}] &= \rm antilog (-6)\\\\&= 10^{-6} \end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%5Crm%20pOH%20%26%3D%2014-%208%20%3D%206%5C%5C%5C%5C%5Crm%20%5BOH%5E%7B-%7D%5D%20%26%3D%20%20%5Crm%20antilog%20%28-6%29%5C%5C%5C%5C%26%3D%2010%5E%7B-6%7D%20%5Cend%7Baligned%7D)
The concentration of calcium hydroxide is calculated as:
![\begin{aligned} &= \dfrac{1}{2} \times \rm [OH^{-}]\\\\&= 5 \times 10^{-4} \;\rm M\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%26%3D%20%5Cdfrac%7B1%7D%7B2%7D%20%5Ctimes%20%5Crm%20%5BOH%5E%7B-%7D%5D%5C%5C%5C%5C%26%3D%205%20%5Ctimes%2010%5E%7B-4%7D%20%5C%3B%5Crm%20M%5Cend%7Baligned%7D)
Therefore, the pH and the pOH give the concentration of the hydrogen or the hydronium ion and the hydroxide ion.
Learn more about pH and pOH here:
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<span>Technetium (TC)- Transition metal.Promethium (Pm)- Rare earth metal.<span>Polonium (Po)- Metalliod.
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Radioactivity tracers,</span>fission products,<span>controls fission reactions
</span><span>Isotopes are variants of a particular chemical element which differ in neutron number. All isotopes of a given element have the same number of protons in each atom.
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For example<span>, the </span>half-life<span> of a radioactive substance is the amount of time it takes for </span>half<span> of its atoms to decay, and the </span>half-life<span> of a drug is the amount of time it takes before </span>half<span> of the active elements are either eliminated or broken down by the body.</span>
Answer: Crocodile is a reptile whereas sheep and gorilla are the mammals.
Explanation:
Crocodile, sheep, and gorilla have alimentary canal in their digestive system. The urea is the common excretory waste.
Mouth is typically large in case of crocodile and comparatively small in sheep and gorilla.
In crocodile more sharp teeth are present as compared to sheep and gorilla for mastication of food and capturing the prey like fish or large animals like zebra.
The crocodile palate is more stronger than sheep and gorilla because it enable it to chew the bones of the prey.
