When acids react with water, H ions are released which then combine with water molecules to form H₃O⁺
<span>C. C4H8
Given that the number of moles of CO2 and H2O produced from the combustion are equal, that means for every carbon atom, there are 2 hydrogen atoms because CO2 has only 1 carbon atom and H2O has 2 hydrogen atoms. So let's look at the available choices and see which one is correct.
A. C2H2
This is a 1 to 1 ratio of carbon to hydrogen. Wrong answer.
B. C2H6
This is a 1 to 3 ratio of carbon to hydrogen. Wrong answer.
C. C4H8
This is a 1 to 2 ratio of carbon to hydrogen. Correct answer.
D. C6H6
This is a 1 to 1 ratio of carbon to hydrogen. Wrong answer.</span>
Mass of metal piece is 611 g and volume of graduated cylinder is 25.1 mL. When metal piece is placed in the graduated cylinder water level increases to 56.7 mL. The increase in volume is due to volume of metal piece that gets added to the volume of water.
Thus, volume of metal piece can be calculated by subtracting initial volume from the final one.

Thus, volume of metal piece will be 31.6 mL. The mass of metal piece is given 611 g, density of metal can be calculated as follows:

Therefore, density of metal is 19.33 g/mL.
Answer:
Ferric oxide reacts with aluminium to produce aluminium oxide and iron. The balanced chemical equation for the given reaction is : Fe2O3 + 2Al → Al2O3 + 2Fe.