Answer:
pH = 3.49
Explanation:
We have a buffer system formed by a weak acid (HNO₂) and its conjugate base (NO₂⁻ coming from KNO₂). We can calculate the pH of a buffer ssytem using the Henderson-Hasselbach equation.
pH = pKa + log [base] / [acid]
pH = -log Ka + log [NO₂⁻] / [HNO₂]
pH = -log 4.50 × 10⁻⁴ + log 0.290 M / 0.210 M
pH = 3.49
When iron rusts and forms iron oxide, the iron oxide has more mass than the iron because there are more iron atoms in iron oxide than in pure iron.
The process of rust occurs when pure iron is exposed to air and moisture. Rust is the oxidation of pure iron to iron II oxide (Fe2O3).
We can see that there are two iron atoms per mole of Fe2O3 whereas there is only one iron atom in each mole of pure iron.
Therefore, iron oxide has more mass than the iron because there are more iron atoms in iron oxide than in pure iron.
Learn more; brainly.com/question/18376414
Explanation:
Water is a polar solvent as the hydrogen and oxygen atom has large difference in their electronegativities.
Oxygen atom is highly electronegative as compared to hydrogen atom therefore, it pulls the electrons of hydrogen atom closer towards itself.
As a result, two poles will create forming a partial positive charge on the hydrogen atom and partial negative charge on the oxygen atom.
Thus, we can conclude that high electronegativity difference between oxygen and hydrogen is the cause of polarity in water molecules.
Answer:
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Explanation:
Answer:
87.15%
Explanation:
To find percent yield, we can use this simple equation

Where "Actual" is the amount in grams actually collected from the reaction, and "Theoretical" is, well, the theoretical amount that should have been produced.
They give us these values, so to find the percent yield, just plug the numbers in.

So, the percent yield is 87.15%
An easy trick to remember how to do this is just to divide the smaller number by the bigger number and move the decimal back two places. If you have a percent yield greater than 100%, something is wrong in the reaction.