A student dissolved a 0.139 g sample of oxalic acid, H2 C2 O4 , in water in an Erlenmeyer flask. Then the student titrated the H2 C2 O4 solution in the flask with a solution of KMnO4 , which has a dark purple color. The balanced chemical equation for the reaction that occurred during the titration is shown above. Identify the species that was reduced in the titration reaction. Justify your answer in terms of oxidation numbers.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

the cold front replaces the warmer air at the ground level changing the wind to be breezy and denser.there is also an immediate drop in the temperature.