Answer:
2L of water.
Explanation:
To know the volume of water to be added to the initial solution, first let us calculate the volume of the final solution. This is illustrated below:
Data obtained from the question:
Initial volume (V1) = 2L
Initial concentration (C1) = 6mol/L
Final concentration (C2) = 3mol/L
Final volume (V2) =?
Using the dilution formula, we can obtain the final volume of the stock as follow:
C1V1 =C2V2
6 x 2 = 3 x V2
Divide both side by 3
V2 = (6 x 2)/3
V2 = 4L.
The final volume of the solution is 4L.
To obtain the volume of water added, we shall determine the change in the volume of the solution. This is illustrated below:
Initial volume (V1) = 2L
Final volume (V2) = 4L
Change in volume = V2 – V1 = 4 – 2 = 2L.
Therefore, 2L of water must be added to the initial solution.
Answer: 59 grams
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Given: mass of hydrogen = 6.6 g
mass of oxygen = 52.4 g
Mass of products = Mass of hydrogen + mass of oxygen = 6.6 +52.4 = 59 g grams
Thus mass or reactant = mass of water
Mass of reactants = mass of products = 59 g
Thus the mass of water initially present was 59 g.
The family on the periodic table that has a filled outer
energy level is VIIIA. The answer is letter D. They are also called the noble
gases or inert gases. They are virtually unreactive towards other elements or
compounds. They are found in trace amounts in the atmosphere. Their elemental form
at room temperature is colorless, odorless and monatomic gases. They also have
full octet of eight valence electrons in their highest orbitals so they have a
very little tendency to gain or lose electrons to form ions or share electrons with
other elements in covalent bonds.
