The thing that governs whether a reaction is exothermic is the energy given out / used up to break / form the bonds in the reaction.
<span>When two substances react, the bonds in those substances first break up, releasing energy, before re-forming in a different way, taking in energy. The nature of the bonds that are broken up and reformed determines whether more energy is given out (exothermic) or taken in (endothermic)</span>
Answer:
237.8L of water would need to be added.
Explanation:
The first thing to do is to identify that the equation to be used is M1V1=M2V2. (This equation works because it turns everything into moles which can then be compared).
Then figure out what information you have and what is being found. In this case:
M1 = 54.7 M
V1 = 1092 mL = 1.092 L
M2 = 0.25 M
V2 = unknown
Then solve the equation for whatever you are trying to find.
M1V1=M2V2
V2=M1V1/M2
Now you need to plug everything in.
V2=(54.7M*1.091L)/0.25M
V2=238.93L
That means that the solution needs a volume of 238.7L to gain a molarity of 0.25M but the starting solution already had a volume of 1.092 L meaning that to find the amount of solvent that needs to be added you just subtract the starting volume by the volume that the solution needs to be.
238.93L - 1.091L = 237.8L
Therefore the answer is that 237.8L needs to be added to a 1.092L 54.7M NaCl solution to make the concentration 0.25M.
I hope this helps. Let me know if anything is unclear.
Answer:
Explanation:
Part a
Normal Phase Chromatography
In the normal phase chromatography, the eluting power is highest for the solvent which has the highest polarity.
So from the given solvents as Methanol, Dichloromethane and Ethyl Acetate
the relative polarities are given as
Methanol=0.762
Dichloromethane (methylene chloride)=0.309
Ethyl Acetate=0.228
So the numbers are given as
Methanol :1
Dichloromethane (methylene chloride):2
Ethyl Acetate:3
Reverse Phase Chromatography
In the reverse phase chromatography, the eluting power is highest for the solvent which has the lowest polarity.
So from the given solvents as diethyl ether , water and toluene
the relative polarities are given as
Diethyl ether=0.117
Water=1.0
Toluene=0.099
So the alphabets are given as
Toluene :A
Diethyl ether: B
Water:C
Answer:
d = 1.85 g/cm³
Explanation:
Given data:
Volume of sulfuric acid = 35.4 mL
Mass of sulfuric acid = 65.14 g
Density of sulfuric acid = ?
Solution:
1 ml = 1cm³
Formula:
d = m/v
d = 65.14 g / 35.2 cm³
d = 1.85 g/cm³