Eli states that sodium phosphate is a mixture because it is composed of both sodium ions and phosphate ions. Which is the best analysis of Eli’s statement?

It is correct because each ion is a pure substance, so sodium phosphate is made up of two pure substances.
It is correct because the composition of sodium phosphate changes depending on the sample.
It is incorrect because sodium phosphate is a compound that has a single composition.
It is incorrect because the two types of ions in sodium phosphate cannot be seen.

It is incorrect because sodium phosphate is a compound that has a single composition.

Explanation:

Sodium phosphate is a compound and not a mixture. It is made up of sodium and phosphate ions and they exists as just a single compound and not different entities.

The parts of a mixture exists separately and they retain their identities.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

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