A. is decomposition so HCL = H2 + Cl2
not balanced cause hcl needs 2
2HCL = H2 + Cl2
balanced
b. Br2 + Al-i = AlBr3 + I2 single rep.
not balanced since br need 3 so watch carefully cause many changes needed
3Br2 + Al-i = AlBr3 + I2 not right is unbalanced so make it 2
3Br2 + Al-i = 2AlBr3 + I2 now left Al is unbal. so make 2 there
3Br2 + 2Ali = 2AlBr3 + I2
Balanced
C. Na + S = Na2S synthesis reaction is not bal. left Na needs 2
2Na + S = Na2S balanced.
Answer:
The correct answer is: <em>They each partially describe the bonding in a molecule.</em>
Explanation:
Some chemical molecules cannot be described completely by using only one Lewis structure. In these cases, we can describe the molecule by drawing 2 or more Lewis structures, and the structures are called <u>resonance structures</u>. The overall molecular structure is explained by all the resonance structures together. So, they each describe the bonding in the molecule only partially.
<u>Answer:</u> The number of carbon and oxygen atoms in the given amount of carbon dioxide is
and
respectively
<u>Explanation:</u>
To calculate the number of moles, we use the equation:

Given mass of carbon dioxide gas = 3.45 g
Molar mass of carbon dioxide gas = 44 g/mol
Putting values in above equation, we get:

1 mole of carbon dioxide gas contains 1 mole of carbon and 2 moles of oxygen atoms.
According to mole concept:
1 mole of a compound contains
number of molecules
So, 0.0784 moles of carbon dioxide gas will contain
number of carbon atoms and
number of oxygen atoms
Hence, the number of carbon and oxygen atoms in the given amount of carbon dioxide is
and
respectively
We determine the limiting reactant by using the moles present in the equation and the actual moles.
According to equation, ratio of Fe₂O₃ : Al = 1 : 2
Actual moles of Fe₂O₃ = 187.3 / (56 x 2 + 16 x 3)
= 1.17
Actual moles of Al = 94.51 / 27
= 3.5
Fe₂O₃ is limiting. Fe₂O₃ required:
(moles Al)/2 = 3.5/2 = 1.75
Moles to be added = 1.75 - 1.17
= 0.58
Mass to be added = moles x Mr
= 0.58 x (56 x 2 + 16 x 3)
= 92.8 grams