Nomenclature and common formula. When part of a salt, the formula of the acetate ion is written as CH3CO2−, C2H3O2−, or CH3COO−. Chemists abbreviate acetate as OAc− or, less commonly, AcO−. Thus, HOAc is the abbreviation for acetic acid, NaOAc for sodium acetate, and EtOAc for ethyl acetate.
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:
The percent by mass of water in this crystal is:
Explanation:
This exercise can be easily solved using a simple rule of three where the initial weight of the hydrated crystal (6,235 g) is taken into account as 100% of the mass, and the percentage to which the mass of 4.90 g corresponds (after getting warm). First, the values and unknown variable are established:
- 6,235 g = 100%
- 4.90 g = X
And the value of the variable X is found:
- X = (4.90 g * 100%) / 6,235 g
- X = approximately 78.6%.
The calculated value is not yet the percentage of the water, since the water after heating the glass has evaporated, therefore, the remaining percentage must be taken, which can be calculated by subtraction:
- Water percentage = Total percentage - Percentage after heating.
- <u>Water percentage = 100% - 78.6% = 21.4%</u>
Answer:
1. No 1 looks like a statement and not a question.
2.Ionic compounds are usually formed from the transfer of electrons from metals to Non metals. All others are Ionic compounds except HCl(Its a covalent compound).
3. The Formula would be K2S. Exchange of Radicals takes place. Sulphur has a -2 charge and potassium has a +1 charge. when they both exchange radicals... The compound is K2S.
4.Group 1 elements have only 1 electron in their outermost shell.
5. its charge will be +1 because it loses the 1 electron in its outermost shell.
6.Group 2 elements have 2electrons in their Valence shell.
7.Already answered. same as No 5.
8. Group 16;Also known as group 6. They have only 6 electrons in their outermost shell.
9.When they want to become stable... they acquire 2electrons to complete their octet... so they possess a -2 charge by forming an ion.
10. i)They form ions when Dissolve in solutions
ii) They are hard and brittle
iii) They have high boiling points
