Answer:
0.88g
Explanation:
The reaction equation:
2NaI + Cl₂ → 2NaCl + I₂
Given parameters:
Mass of Sodium iodide = 2.29g
Unknown:
Mass of NaCl = ?
Solution:
To solve this problem, we work from the known to the unknown.
First find the number of NaI from the mass given;
Number of moles =
Molar mass of NaI = 23 + 126.9 = 149.9g/mol
Now insert the parameters and solve;
Number of moles =
= 0.015mol
So;
From the balanced reaction equation;
2 moles of NaI produced 2 moles of NaCl
0.015mole of NaI will produce 0.015mole of NaCl
Therefore;
Mass = number of moles x molar mass
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
Now;
Mass of NaCl = 0.015 x 58.5 = 0.88g
Heat needed=mcθ
=7×0.031×(42-17)
=5.425cal
Answer: option <span>C. the total energy inside the calorimeter will decrease.
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Justification:
The answer is a direct application of the first law of thermodynamic (the law of conservation of energy).
By telling that the t<span>he calorimeter is sealed so that there is no heat exchanged between the contents of the container and the surrounding air, the first law of thermodynamics implies that the total energy inside the calorimeter will not change.
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<span>That statement, without adding any more is enough justification.
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Regarding, the other statements, you can show they are true:
<span>A.
the thermometer will show an increase in temperature.
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</span><span>Since the reaction is exothermic, the heat released will increase the temperature inside the sealed calorimeter,which, of course, is shown by the termometer.
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</span><span>B. The potential
energy of the products will be lower than that of the reactants.
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</span><span>
</span><span>In any exothermic reaction, the potential energy of the products is lower than that of the reactants, because the heat released is lost by the reactants when they react and transform into the products.
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</span><span>
</span><span>D. The water
increases in temperature as the reaction gives off heat</span>.
Sure. The heat cannot leave the sealed calorimeter, but the water inside the calorimeter will absorb that heat: the molecules of water will gain kinetic energy and so its temperature will be increase.
Answer:
Electrons, with a charge of -1.
Explanation:
The nucleus of the atom is composed of protons and neutrons.
The nucleus is where the bulk of the mass of an atom is found.
Electrons orbit the nucleus in various energy levels.
Protons have a charge of +1, neutrons have no charge, and electrons have a charge of -1.
Greetings I am DemonicPresence, the answer would be A.