M1m1 = M2m2
where M1 is the concentration of the stock solution, m1 is the mass of the stock solution, M2 is the concentration of the new solution and m2 is its new mass.
M1m1 = M2m2
.925(m1) = .35(250)
m1 = 94.59 g
Answer: 94.59 grams of 92.5 % by mass solution will be needed.
Explanation:
Mass of sulfuric acid is 250 grams of 35 % by mass solution:
Mass of in 250 g of 35 % solution = 87.5 g
Mass of 92.5 % needed to make 35 % by mass solution.
Mass of the solution required = 94.59 g
94.59 grams of 92.5 % by mass solution will be needed.
Answer:
0.024M
Explanation:
Data obtained from the question include:
C1 = 6M
V1 = 2mL
C2 =?
V2 = 500mL
The molarity of the diluted solution can be obtained as follows:
C1V1 = C2V2
6 x 2 = C2 x 500
Divide both side by 500
C2 = (6 x 2) /500
C2 = 0.024M
The molarity of the diluted solution is 0.024M
Answer:
The molarity is 0.024 mol / L
Explanation:
Molarity = Number of moles / Volume of solution
= (6.0 mol/L x 2.0 x L) / 0.500 L
= 0.024 mol / L
Answer:
+60 kJ
Explanation:
Activation energy = PE(AB) - PE(A+B) = 100 -40 = +60 kJ
b. False
Explanation:
Burning of alcohol produces different products as it depends on the type and nature of alcohol which is being burnt.
Some alcohols upon burning produce toxic gases or products whereas some alcohols on burning does not produce any toxic substances.
For example, when ethanol is burnt then it reacts with oxygen and results in the formation of water and carbon dioxide.
Thus, we can conclude that the statement burning alcohol for fuel is a very efficient process is a false statement.
9.3 %
30%
7.5%
Answer:
percent by mass = 79%
Explanation:
Data Given:
mass of solute (Na₂CO₃) = 75 g
mass of solvent ( water ) = 20 g
mass percent of solution = ?
Solution:
Formula used to find percent by mass
mass of solute / mass of solution x 100 . . . . . . (1)
first we have to find mass of solution
mass of solution = mass of solute + mass of Solvent . . . . (2)
put values in equation 2
mass of solution = 75 g + 20 g
mass of solution = 95 g
Now,
put values in equation 1
Percent by mass = mass of solute / mass of solution x 100
Percent by mass = 75 g / 95 g x 100
Percent by mass = 79 %
so,
The percent of the solution by mass = 79%
***Note:
The same work can be used for the other values too i.e. if you have 20 g of solute and 75 g solvent.
Answer:
The answer is 78.9%
Explanation:
The percentage weight in volume indicates the mass of solute per volume. We will use the% weight/volume formula to calculate what the exercise asks for, as follows:
%
The mass of an atom comes from the protons and neutrons that are found in the nucleus. The number of protons is the atomic number of an element. To find the number of neutrons, subtract the atomic number from the mass of an atom. The atomic number is 8 and the atomic mass is 16.