Answer:
0.00735°C
Explanation:
By seeing the question, we can see the elevation in boiling point with addition of BaCl₂ in water
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<u>The</u><u> </u><u>elevation</u><u> </u><u>in</u><u> </u><u>boiling</u><u> </u><u>point</u><u> </u><u>is</u><u> </u><u>a</u><u> </u><u>phenomenon</u><u> </u><u>in</u><u> </u><u>which</u><u> </u><u>there</u><u> </u><u>is</u><u> </u><u>increase</u><u> </u><u>in</u><u> </u><u>boiling</u><u> </u><u>point</u><u> </u><u>in</u><u> </u><u>solution</u><u>,</u><u> </u><u>when</u><u> </u><u>the</u><u> </u><u>particular</u><u> </u><u>type</u><u> </u><u>of</u><u> </u><u>solute</u><u> </u><u>is</u><u> </u><u>added</u><u> </u><u>to</u><u> </u><u>pure</u><u> </u><u>solvent</u><u>.</u>
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Where 'i' is van't hoff factor which represents the ratio of observed osmotic pressure and the value to be expected.
and 'i' is 3 (as given in the question)
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'Kb' is molal boiling point constant. And it's value is 0.51°C/mol(given in question)
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'm' represent the molality of solution. Molatity is no. of moles of solution present in 1kg of solution.
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<u>To</u><u> </u><u>find</u><u> </u><u>molality</u><u>,</u><u> </u><u>we</u><u> </u><u>have</u><u> </u><u>to</u><u> </u><u>divide</u><u> </u><u>no</u><u>.</u><u> </u><u>of</u><u> </u><u>moles</u><u> </u><u>of</u><u> </u><u>solute</u><u> </u><u>by</u><u> </u><u>weight</u><u> </u><u>of</u><u> </u><u>solution</u>
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While first we need to no. of moles

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<u>Now</u><u>,</u><u> </u><u>we</u><u> </u><u>will</u><u> </u><u>find</u><u> </u><u>molality</u>
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<u>Henceforth</u><u>,</u><u> </u><u>the</u><u> </u><u>change</u><u> </u><u>in</u><u> </u><u>boiling</u><u> </u><u>point</u><u> </u><u>is</u><u> </u><u>0</u><u>.</u><u>0</u><u>0</u><u>7</u><u>3</u><u>5</u><u>°</u><u>C</u><u>.</u>
Answer:
O The number of oxygen atoms in the reactants used by this process equals the total number of oxygen atoms in the products.
Explanation:
The statement that best describes how photosynthesis follows the law of conservation of mass is that the number of oxygen atoms in the reactants used by this process is equal to the total number of oxygen atoms in the products.
The equation of photosynthesis reaction is given as:
6CO₂ + 6H₂O → C₆ H₁₂ O₆ + 6O₂
According to the law of conservation of mass, matter is neither created nor destroyed during the course of a chemical reaction.
By the virtue of this, the number of oxygen atom on both sides of the expression must be the same. Also, the number of carbon and hydrogen atoms must also be the same.
The volume of the 18M HCl needed to make the solution will be 2.5 mL.
<h3>Dilution</h3>
According to the dilution principle, the number of moles of solutes in a solution before and after dilution must remain the same.
Since, mole = molarity x volume
Thus, molarity x volume before dilution = molarity x volume after dilution.
Mathematically, the equation is written as: m1v1 = m2v2
In this case, m1 = 18 M, m2 = 1.5 M, and v2 = 30 mL.
What we are looking for is v1, the amount of the stock HCl needed for dilution.
v1 = m2v2/m1 = 1.5 x 30/18 = 2.5 mL.
Thus, 2.5 mL of the stock HCl would be needed.
More on dilution can be found here: brainly.com/question/21323871
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