The coefficients are the whole numbers written before the substances to obey the Law of Conservation of Mass, or more specifically, the Law of Definite Proportions. You have to make sure that the number of each substance before and after the reaction must be the same. Thus, the given reaction is already balanced. <em>The coefficient for each substance in the reaction is 1</em>. When no coefficient is written, it is by default equal to 1.
The chemicals or substance get more corrosive.
D) Physical Change, I would argue, because you can reverse this change by boiling off (evaporating) the water. But there are arguments for both physical and chemical change being what occurs.
A physical change results in a change of the material's appearance, but no new chemical products result. A chemical change involves a chemical reaction, with new substances produced as a result of the change.
Answer:
acid
Explanation:
solution with pH less than 7 is acid
those with more that 7 is base
those equal to 7 is neutral
Answer:
11.1mL
Explanation:
The reaction expression is given as:
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
Given parameters:
density of ethanol = 0.789g/mL
mass of CO₂ = 25g
Unknown:
Volume of ethanol = ?
Solution:
First find the number of moles of the CO₂ from the given mass;
Number of moles =
Molar mass of CO₂ = 12 + 2(16) = 44g/mol
Number of moles = = 0.57mol
Then;
Find the number of moles of ethanol used;
3 moles of CO₂ is produced from 1 mole of ethanol;
0.57mole of CO₂ will be produced from = 0.19mole of ethanol
Now;
Find the mass of the ethanol from the given mole;
Mass of ethanol = number of moles x molar mass
Molar mass of ethanol = 2(12) + 5(1) + 16 + 1 = 46g/mol
Mass of ethanol = 0.19 x 46 = 8.74g
Then;
Density is the mass per unit volume of a substance;
Density =
Volume =
Volume = = 11.1mL