A scientist is attempting to check the relative atomic masses on the periodic table. He works with three different compounds that contain only C and another compound. These are diatomic compounds with a formula of CX. He finds the following information. If he assumes the weight of C is 12 what is the weight of the other element (X1, X2, X3) and what is the identity of each unknown element? Compound 1 Compound 2 Compound 3
Wt C Wt X 4.2 4.9 3.5 4.67 1.3 3.47

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.

hope this !

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.