Which of the following is a correctly balanced equation?
A.
2Cu + O2 -- 2CuO

B.
Mg + O2 -- MgO2

C.
3KCl + HNO3 -- 3HCl + KNO3

D.
CaCO3 -- CaO + CO3

Question

Which of the following is a correctly balanced equation?
  A.
2Cu + O2  --> 2CuO

  B.
Mg + O2 --> MgO2

  C.
3KCl + HNO3 --> 3HCl + KNO3

  D.
CaCO3 --> CaO + CO3

anonymous · Answer

@sleepyjess

anonymous · Answer

@Hero @tkhunny

tkhunny · Answer

Why do we get no work shown when we are tagged.  SHOW YOUR WORK.  You can't have nothing.

This is an addition problem.  Did you lose or gain any molecules at the "-->"?

tkhunny · Answer

You will also need to try harder in the notation.  Subscripts are important.

anonymous · Answer

okay actually nvm I figured it out! Thank you for the advice though!