<span>This question can best be answered using a Periodic Table of Elements. All the elements are listed by their atomic number starting from the top left and moving right and down the table. Starting at element 8, you will find Oxygen with a mass of 15.99 amu, followed by element 9 Fluorine with a mass of 18.99 , element 10 Neon with a mass of 20.18 , element 11 Sodium with a mass of 22.99. Writing them with their symbols you would have; O, F, Ne, Na.</span>
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:
7.51 × 10¹⁷
Explanation:
1. Calculate the <em>energy of one photon</em>
The formula for the energy of a photon is
E = hc/λ
h = 6.626 × 10⁻³⁴ J·s; c = 2.998 × 10⁸ m·s⁻¹
λ = 531 nm = 531 × 10⁻⁹ m Insert the values
E = (6.626 × 10⁻³⁴ × 2.998× 10⁸)/(531 × 10⁻⁹)
E = 3.741× 10⁻¹⁹ J
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2. Calculate the number of photons
Divide the total energy by the energy of one photon.
No. of photons = 0.281 × 1/3.741 × 10⁻¹⁹
No. of photons = 7.51 × 10¹⁷ photons
Answer:I believe it’s because of the volcanos making up the ring
Explanation:
Catalysts are substances that speed up the rate of a chemical
reaction. It is important to know that reacting species must first possess a
minimum amount of energy equal to the activation energy for the reaction
to proceed. The catalyst works in a way that lowers the activation energy
required for the reaction to proceed. In this way, the reaction occurs at a
faster rate than without a catalyst. Catalysts do not react with
the chemical species in the reaction, thus, they are not consumed. However, over
time, catalysts tend to degrade and their function is also reduced. When this
happens, new catalysts replace the poisoned ones. Catalysts are widely used
today since they bring an increase in the production rate of commercial chemicals.