Answer:
+8 J/mol
Explanation:
The following were obtained from the question:
Mole of the compound = 3 moles
Heat Energy used = 24J
Hreaction =?
The heat of reaction is the energy released or absorb during a chemical reaction. It is can obtained mathematically by the following equation:
Hreaction = Heat energy/mole
With the above equation, we can easily find the Hreaction for the question given as follow:
Hreaction = Heat energy/mole
Hreaction = 24J / 3mol
Hreaction = 8 J/mol
Since the compound used the energy, the Hreaction is +8 J/mol
A, as carbon is an atomic substance - element
Answer:
The mass of water to be added is 2 pounds
Explanation:
The given parameters are;
The mass of the given solution = 2 pounds
The concentration of the given solution = 30%
The desired concentration of the solution = 15%
The mass, m of the acetic acid in the given solution = 30% × 2 pounds
m = 30/100 × 2 pounds = 0.6 pounds
To make a 15% acetic acid solution of acetic acid, the mass X of the required volume, is given as follows;
15% of X = 0.6 pounds
15/100 × X = 3/20 × 0.6 pounds
∴ The mass of the solution required X = 0.6 × 20/3 = 4 pounds
The mass of the solution that will contain 0.6 pounds of acetic acid giving a 15% acetic acid solution is 4 pounds
Therefore, the mass of water to be added to the original solution to make the a 15% acetic acid solution is 2 pounds.
Answer: a piece of pure matter which we can see from our naked eye is termed as a substance
Explanation:
every substance has physical and chemical properties like;
diamond ,water ,pure sugar ,table salt e.t.c
an element is a substance made up of same type of atoms having same atomic number[protons],and cannot be easily decomposed in to a single substance by ordinary chemical reaction example,.....
gold,copper,zinc and some are in liquid form like mercury,bromine and some are in gases for example, hydrogen ,oxygen, nitrogen
