When you have a chemical reaction, it means something goes wrong with your chemicals.
A) because when gas is produced it changes chemical form whereas the chemical change is obvious.
Answer:
1) C2H4(OH)2
Explanation:
A 1,2-ethanediol has an ethane structure consisting of two Carbon atoms with a hydrogen from each carbon substituted by a hydroxyl group. This makes it a 1,2-diol.
Are there any choices? Because from what the question is it seems like we need choices to help
Answer: 0.9375 g
Explanation:
To calculate the number of moles for given molarity, we use the equation:
.....(1)
Molarity of 
solution = 0.75 M
Volume of solution = 25.0 mL = 0.025 L
Putting values in equation 1, we get:
According to stoichiometry :
2 moles of require = 1 mole of 
Thus 0.01875 moles of will require=
of
Mass of 
Thus 0.9375 g of is required to react with 25.0 ml of 0.75 M HCl
