<span>The first method to determine the chemical composition of a substance in space was using light. By determining red shift in the observed spectrum of light they could determine the elements they were observing. Different elements change the way light behaves and from this scientists can determine the makeup of things such as stars and nebulas.</span>
Answer: 
Explanation:

cM 0 0
So dissociation constant will be:

Given: c = 0.15 M
pH = 1.86
= ?
Putting in the values we get:
Also ![pH=-log[H^+]](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%2B%5D)
![1.86=-log[H^+]](https://tex.z-dn.net/?f=1.86%3D-log%5BH%5E%2B%5D)
![[H^+]=0.01](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D0.01)
![[H^+]=c\times \alpha](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3Dc%5Ctimes%20%5Calpha)


As ![[H^+]=[ClCH_2COO^-]=0.01](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D%5BClCH_2COO%5E-%5D%3D0.01)

![K_a=1.67\times 10^{-3]](https://tex.z-dn.net/?f=K_a%3D1.67%5Ctimes%2010%5E%7B-3%5D)
Thus the vale of
for the acid is 
Answer:
AsF3:C2CI6
4:3
1.3618 moles: 1.02135 moles(1.3618÷4×3)
C2CI6 is the limting reagent
So the number of moles for AsCI3 is 0.817 moles( number of moles of the limting reagant) ÷3 ×4 (according to ratio by balancing chemical equation)=1.09 moles(3 s.f.)
or
Balanced equation
4AsF3 + 3C2Cl6 → 4AsCl3 + 3C2Cl2F4
Use stoichiometry to calculate the moles of AsCl3 that can be produced by each reactant.
Multiply the moles of each reactant by the mole ratio between it and AsCl3 in the balanced equation, so that the moles of the reactant cancel, leaving moles of AsCl3.
Explanation:
Answer:
The solution is always homogeneous mixture and transparent through which the light can travel. The mixture of water and sugar is a solution because sugar is soluble in water and form homogeneous mixture while the sand can not dissolve in water and sand particles scatter the light.
Explanation:
Solution:
"The solution is always homogeneous mixture and transparent through which the light can travel"
The mixture of water and sugar is a solution because sugar is soluble in water and form homogeneous mixture. The solubility of sugar is high as compared to the sand in water because the negative and positive ends of sucrose easily dissolve into the polar solvent i.e, water
Suspension:
"Suspension is the heterogeneous mixture, in which the solute particles settle down but does not dissolve"
The mixture of water and sand is suspension. The sand can not dissolve in water because it is mostly consist of quartz. The nonpolar covalent bonds of sand are too strong and cannot be break by water molecules.
Answer:
V₂ = 27 L
Explanation:
Given data:
Initial volume = 15 L
Initial temperature = 125 K
Final temperature = 225 K
Final volume = ?
Solution:
The given problem will be solve through the Charles Law.
According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.
Mathematical expression:
V₁/T₁ = V₂/T₂
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
Now we will put the values in formula.
V₁/T₁ = V₂/T₂
V₂ = V₁T₂/T₁
V₂ = 15 L × 225K / 125 k
V₂ = 3375 L.K / 125 K
V₂ = 27 L