All of the above
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Given is the ratio of conjugate base and conjugate acid of phosphoric acid. pH of a substance is the concentration of the hydrogen ions in its solution and higher this concentration lower is the value of pH.
pKa value is a measure of the strength of acid, it is the negative log of acid dissociation constant Ka.
Answer: I am actually studying about Stars, so I got you.
3. As the temperature of a star Increases, it's luminosity increases.
As the temperature of a star decreases, it's luminosity decreases.
4. Hot and Bright. The bigger the star, the hotter it gets is from what I learned.
Given concentration of NaCl=15%
Means ,
In every 100g of Solution 15g of NaCl is present .
Now
So ,



<u>37.5g of NaCl present in 250g of solution.</u>