Answer:
The mass of a sample of iron that has had 300 J applied to it and heats up from 20 degrees Celsius to 40 degrees Celsius is 32.61 grams.
Explanation:
Calorimetry is the measurement and calculation of the measurement of heat changes exchanged by a body or a system produced in physical and chemical processes.
The sensible heat of a body is the amount of heat received or transferred by a body to produce a change in temperature but without a change in physical state.
The sensible heat in a constant pressure is calculated by:
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 is the temperature variation (ΔT=Tfinal - Tinitial)
In this case:
- c= 0.46
- m= ?
- Tfinal= 40 C
- Tinitial= 20 C
Replacing:
300 J= 0.46 * m* (40 - 20) C
Solving:
300 J= 0.46 * m* 20 C
m= 32.61 g
Answer:
c. suggesting a solution to a problem after studying it carefully
Explanation:
Hypothesis generally refers to an assumption made. This assumption can either be true or false. It is a reasoning presented in order to explain a phenomenon and is the starting point for further investigation.
Among the options, the closest that best describes it is option C.
Answer : The cell potential for this reaction is 0.50 V
Explanation :
The given cell reactions is:
The half-cell reactions are:
Oxidation half reaction (anode): 
Reduction half reaction (cathode): 
First we have to calculate the cell potential for this reaction.
Using Nernest equation :
![E_{cell}=E^o_{cell}-\frac{2.303RT}{nF}\log \frac{[Zn^{2+}]}{[Pb^{2+}]}](https://tex.z-dn.net/?f=E_%7Bcell%7D%3DE%5Eo_%7Bcell%7D-%5Cfrac%7B2.303RT%7D%7BnF%7D%5Clog%20%5Cfrac%7B%5BZn%5E%7B2%2B%7D%5D%7D%7B%5BPb%5E%7B2%2B%7D%5D%7D)
where,
F = Faraday constant = 96500 C
R = gas constant = 8.314 J/mol.K
T = room temperature = 
n = number of electrons in oxidation-reduction reaction = 2
= standard electrode potential of the cell = +0.63 V
= cell potential for the reaction = ?
![[Zn^{2+}]](https://tex.z-dn.net/?f=%5BZn%5E%7B2%2B%7D%5D)
= 3.5 M
![[Pb^{2+}]](https://tex.z-dn.net/?f=%5BPb%5E%7B2%2B%7D%5D)
= 
Now put all the given values in the above equation, we get:
Therefore, the cell potential for this reaction is 0.50 V
Explanation:
gravity if it's incorrect sorry
Here's link to the answer:
tinyurl.com/wpazsebu
