Question

please help!!
Mg(HSO3)2 decomposes into a solid X, H2O vapor, and SO2 gas. If 186 g of Mg(HSO3)2 decomposes completely and leaves behind 40 g of solid X, what is the identity of X?

Answer 1

Hm, let me think about this one.

Answer 2

I'm stumped too

Answer 3

The molar mass of the compound is about 186g.

Answer 4

molar mass of Mg(HSO3)2 is 146.339g

Answer 5

How do you get that?

Answer 6

oh wait sorry you're right it's 186.45g!

Answer 7

So, we basically need to break it apart and see what we have left.

Answer 8

And since Mg isn't in the two components given, it will need to be at least part of X.

Answer 9

But it's only 24g by itself, so that can't be it.

Answer 10

The H2O takes 2 H and 1 O, leaving 2 S and 5O.

Answer 11

If we have 2SO2 then 1 O is left over. And MgO is a solid compound that is about 40g.

Answer 12

here are the choices

Answer 13

@JoannaBlackwelder @abmon?

Answer 14

Mg(HSO3)2-->X+H2O+2SO2
Molar Mass:186.4473 Mass given: 186 Number of moles=Mass(g)/Molar Mass(g/mol)=1 mole of Mg(HSO3)2
when we balance 2 moles are produced and 1 mole of H2O so we are left with one Mg and one Oxygen so i go with choice MgO

Answer 15

got it! thank you! @Abmon98

Answer 16

your welcome :) but i had a method using calculation i will try it out and see if it works

Answer 17

ok :)