2Li+2H2O—>2LiOH+H2
1 answer:
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Answer:
The specific heat capacity of the unknown metal is 0.223
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
There is a direct proportional relationship between heat and temperature. The constant of proportionality depends on the substance that constitutes the body as on its mass, and is the product of the specific heat by the mass of the body. So, the equation that allows calculating heat exchanges is:
Q = c * m * ΔT
where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.
In this case, you know:
- Q= 418.6 J
- c= ?
- m= 75 g
- ΔT= 25 C
Replacing:
418.6 J= c* 75 g* 25 C
Solving:
c= 0.223
<u><em>The specific heat capacity of the unknown metal is 0.223 </em></u><u><em></em></u>
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Answer:
5.56 × 10⁻⁸
Explanation:
Step 1: Given data
- Concentration of the weak acid (Ca): 0.187 M
- pH of the solution: 3.99
Step 2: Calculate the concentration of H⁺
We will use the following expression.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -3.99 = 1.02 × 10⁻⁴ M
Step 3: Calculate the acid dissociation constant (Ka)
We will use the following expression.