Answer:
2.03
Explanation:
Let's <u>assume we have 1 L of the solution</u>:
- There would be 2.07 ethylene glycol moles.
- The solution would weigh (1000 mL * 1.02 g/mL) = 1020 g.
With that information we can <u>calculate the molality</u>:
- molality = moles of solute / kg of solvent
- molality = 2.07 moles / (1020 ÷ 1000) = 2.03 m
Keep in mind that this is only an estimate, as we used the kg of the solution and not of the solvent.
Answer: Combustion
Explanation:
Methane gas or natural gas is the hydrocarbon that reacts with oxygen as shown below: CH4 + 2O2 → CO2 + 2H2O There are two types of combustion reactions: complete and incomplete combustion. Therefore there are four products, carbon dioxide, water, carbon, and carbon monoxide.
Answer:
Oiling is done on a regular basis to sewing Machine because in the machine there are lots of machinery parts i.e. wheels and axels, etc. which are in continuous use and they possess so much frictional force between them that wear tear may be observed in those parts.
Answer: Dissociation constant of the acid is 
.
Explanation: Assuming the acid to be monoprotic, the reaction follows:
pH of the solution = 6
and we know that
![pH=-log([H^+])](https://tex.z-dn.net/?f=pH%3D-log%28%5BH%5E%2B%5D%29)
![[H^+]=antilog(-pH)](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3Dantilog%28-pH%29)
![[H^+]=antilog(-6)=10^{-6}M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3Dantilog%28-6%29%3D10%5E%7B-6%7DM)
As HA ionizes into its ions in 1 : 1 ratio, hence
![[H^+]=[A^-]=10^{-6}M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D%5BA%5E-%5D%3D10%5E%7B-6%7DM)
As the reaction proceeds, the concentration of acid decreases as it ionizes into its ions, hence the decreases concentration of acid at equilibrium will be:
![[HA]=[HA]-[H^+]](https://tex.z-dn.net/?f=%5BHA%5D%3D%5BHA%5D-%5BH%5E%2B%5D)
![[HA]=0.1M-10^{-6}M](https://tex.z-dn.net/?f=%5BHA%5D%3D0.1M-10%5E%7B-6%7DM)
![[HA]=0.09999M](https://tex.z-dn.net/?f=%5BHA%5D%3D0.09999M)
Dissociation Constant of acid, 
is given as:
![K_a=\frac{[A^-][H^+]}{HA}](https://tex.z-dn.net/?f=K_a%3D%5Cfrac%7B%5BA%5E-%5D%5BH%5E%2B%5D%7D%7BHA%7D)
Putting values of ![[H^+],[A^-]\text{ and }[HA]](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%2C%5BA%5E-%5D%5Ctext%7B%20and%20%7D%5BHA%5D)
in the above equation, we get
Rounding it of to one significant figure, we get
Answer:
28.7 grams of water
Explanation:
Calorimetry problem:
Q = C . m . ΔT
2400 J = 4.18 J/g°C . m . (30°C - 10°C)
2400 J = 4.18 J/g°C . m . 20°C
2400J = 83.6 J/g . m
2400J / 83.6 g/J = m
28.7 g = m
