The answer would be 0.288827452320528
Answer:
= 25 ppm
Explanation:
- PPM also refers to parts per million, it represents a low concentration of a solution. It represents 0.001 gram or a milligram in a 1000 mL, which equivalent to 1 mg per liter.
Given; a sample size of 2000 g contained 0.050 g DDT
It means, 2000 mL sample contained 50 mg DDT
Therefore in ppm we get;
= 50 mg/ 2 L
= 25 mg/L
<u>= 25 ppm</u>
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>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>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 : The correct option is, (2) Energy is absorbed as bonds are broken.
Explanation :
As we know that the bonds are formed and breaks during the chemical reaction. Some energy is released or absorbed when the bonds are formed and breaks during the chemical reaction.
During the bond breaking, some energy is required to break the bonds.
During the bond formation, some energy is released to the formation of the bonds.
In the given reaction, the bond between the hydrogen-hydrogen in 
are breaking into two hydrogen. That means during the bond breaking, some energy is required or absorbed to break the bonds.
Hence, the correct option is, (2) Energy is absorbed as bonds are broken.
balanced equation =
3Cu(OH)2 + 2H3PO4 → Cu3(PO4)2 + 6H2O
