Answer:
7 is the only basic number on a pH scale
The change in temperature of the metal is 6.1°C. Details about change in temperature can be found below.
<h3>How to calculate change in temperature?</h3>
The change in temperature of a substance can be calculated by subtracting the initial temperature of the substance from the final temperature.
According to this question, a 25.0 g sample of metal at 16.0 °C is warmed to 22.1 °C by 259J of energy.
This means that the change in temperature of the metal can be calculated as:
∆T = 22.1°C - 16°C
∆T = 6.1°C
Therefore, the change in temperature of the metal is 6.1°C.
Learn more about change in temperature at: brainly.com/question/19051558
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Answer:
pH=11.
Explanation:
Hello!
In this case, since the data is not given, it is possible to use a similar problem like:
"An analytical chemist is titrating 185.0 mL of a 0.7500 M solution of ethylamine(C2HNH2) with a 0.4800 M solution of HNO3.ThepK,of ethylamine is 3.19. Calculate the pH of the base solution after the chemist has added 114.4 mL of the HNO3 solution to it"
Thus, for the reaction:

Tt is possible to compute the remaining moles of ethylamine via the following subtraction:

Thus, the concentration of ethylamine in solution is:
![[ethylamine]=\frac{0.0816mol}{0.1850L+0.1144L}=0.2725M](https://tex.z-dn.net/?f=%5Bethylamine%5D%3D%5Cfrac%7B0.0816mol%7D%7B0.1850L%2B0.1144L%7D%3D0.2725M)
Now, we can also infer that some salt is formed, and has the following concentration:
![[salt]=\frac{0.0549mol}{0.1850L+0.1144L}=0.1834M](https://tex.z-dn.net/?f=%5Bsalt%5D%3D%5Cfrac%7B0.0549mol%7D%7B0.1850L%2B0.1144L%7D%3D0.1834M)
Therefore, we can use the Henderson-Hasselbach equation to compute the resulting pOH first:
![pOH=pKb+log(\frac{[salt]}{[base]} )\\\\pOH=3.19+log(\frac{0.1834M}{0.2725M})\\\\pOH=3.0](https://tex.z-dn.net/?f=pOH%3DpKb%2Blog%28%5Cfrac%7B%5Bsalt%5D%7D%7B%5Bbase%5D%7D%20%29%5C%5C%5C%5CpOH%3D3.19%2Blog%28%5Cfrac%7B0.1834M%7D%7B0.2725M%7D%29%5C%5C%5C%5CpOH%3D3.0)
Finally, the pH turns out to be:

NOTE: keep in mind that if you have different values, you can just change them and follow the very same process here.
Best regards!
Answer:
81.5g/mol
Explanation:
Molar mass is the ratio between mass of a substance (In this case, 0.207g) and moles presents in this mass.
To solve this question we must find the moles of the gas in order to obtain the molar mass using:
PV = nRT
PV / RT = n
<em>Where P is pressure = 0.980atm</em>
<em>V is volume in Liters = 0.0725L</em>
<em>R is gas constant = 0.082atmL/molK</em>
<em>T is absolute temperature = 68°C + 273.15 = 341.15K</em>
<em />
0.980atm*0.0725L / 0.082atmL/molK*341.15K = n
2.54x10⁻³ moles = n
Thus, the molar mass of the gas is:
0.207g / 2.54x10⁻³ moles
<h3>81.5g/mol</h3>