Answer:
527.184 J of heat is removed from a 21 g water sample if it is cooled from 34.0 ° C to 28.0 ° C.
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
When the heat added or removed from a substance causes a change in temperature in it, this heat is called sensible heat.
In other words, the sensible heat of a body is the amount of heat received or transferred by a body when it undergoes a change in temperature without there being a change in physical state (solid, liquid or gaseous). The equation that allows to calculate this heat exchange is:
Q = c * m * ΔT
Where Q is the heat exchanged by a body of mass m, constituted by a substance of specific heat c and where ΔT=Tfinal-Tinitial is the change in temperature.
In this case:
- c= 4.184
- m=21 g
- ΔT=Tfinal-Tinitial=28 °C - 34 °C=-6 °C
Replacing:
Q= 4.184 * 21 g* (-6 C)
Q= - 527.184 J
To lower the temperature, heat has to be given, for that the final temperature must be lower than the initial temperature; and it receives the name of transferred heat and has a negative value, as in this case.
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527.184 J of heat is removed from a 21 g water sample if it is cooled from 34.0 ° C to 28.0 ° C.</em></u>
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It contains 6.02 mc001-1.jpg 1023 grams of sodium chloride.
It is the mass of 12 carbon atoms.
It contains 6.02 mc001-2.jpg 1023 particles of a given substance.</span>
3. Ampere is the base unit for electric current.
Answer: True
Explanation:
Let's begin by explaining that the vision phenomenon depends on three elements: the observer, the object and the light source.
In addition, objects have pigments, which generally absorb more light than they reflect (they absorb certain wavelengths and reflect others). Therefore, the color that a given object seems to have depends on which parts of the visible electromagnetic spectrum are reflected and which parts are absorbed.
In this sense, the colours we see are in fact the wavelengths that are reflected or transmitted from the object. For example, a red object has that color because when it is illuminated whith white light, the pigments on this object abrsorb all the the wavelengths of the visible electromagnetic spectrum, except red. That is why red light is the only light that is reflected from the mentioned object.
Answer & Explanation:
At high temperatures or in the presence of catalysts, sulfur dioxide reacts with hydrogen sulfide to form elemental sulfur and water. This reaction is exploited in the Claus process, an important industrial method to dispose of hydrogen sulfide.
