The pH meter measure the concentration of the hydrogen(+) ion, and the concentration of Hydroxide(-). Hydrogen is acidic, Hydroxide is basic.
The answer is D.
The proceeds of respiration, where living matter, produces the product of CO2 upon exhalation would be contributing to the Carbon cycle.
<u>Answer:</u> The correct answer is Option B.
<u>Explanation:</u>
Chemical reactivity is defined as the tendency of an element to loose of gain electrons.
Non-metals are the elements which gains electrons and hence, their chemical reactivity will be the tendency to loose electrons.
Their chemical reactivity increases as we move from left to right in a period because the valence shell come closer to nucleus as we move from left to right. So, addition of new electron in the valence shell becomes easier due to greater attraction between nucleus and valence electron.
For the given options:
<u>Option A:</u> Silicon
This element lies in Group 14 and Period 3.
<u>Option B:</u> Chlorine
This element lies in Group 17 and Period 3.
<u>Option C:</u> Sulfur
This element lies in Group 16 and Period 3.
<u>Option D:</u> Phosphorus
This element lies in Group 15 and Period 3.
Hence, chlorine will readily accept electrons due to its position in the periodic table.
Answer:
5:22 am
Explanation:
The gas X decays following a first-order reaction.
The half-life (
) is 25 min. We can find the rate constant (k) using the following expression.
![k = \frac{ln2}{t_{1/2}} =\frac{ln2}{25min} = 0.028 min^{-1}](https://tex.z-dn.net/?f=k%20%3D%20%5Cfrac%7Bln2%7D%7Bt_%7B1%2F2%7D%7D%20%3D%5Cfrac%7Bln2%7D%7B25min%7D%20%3D%200.028%20min%5E%7B-1%7D)
We can find the concentration of X at a certain time (
) using the following expression.
![[X] = [X]_0 \times e^{-k \times t}](https://tex.z-dn.net/?f=%5BX%5D%20%3D%20%5BX%5D_0%20%5Ctimes%20e%5E%7B-k%20%5Ctimes%20t%7D)
where,
: initial concentration of X
t: time elapsed
![\frac{[X]}{[X]_0}= e^{-k \times t}\\\frac{1/10[X]_0}{[X]_0}= e^{-0.028min^{-1} \times t}\\t=82min](https://tex.z-dn.net/?f=%5Cfrac%7B%5BX%5D%7D%7B%5BX%5D_0%7D%3D%20e%5E%7B-k%20%20%5Ctimes%20t%7D%5C%5C%5Cfrac%7B1%2F10%5BX%5D_0%7D%7B%5BX%5D_0%7D%3D%20e%5E%7B-0.028min%5E%7B-1%7D%20%20%5Ctimes%20t%7D%5C%5Ct%3D82min)
The earliest time Professor Utonium can come back to do experiments in the lab is:
4:00 + 82 = 5:22 am