Question 17:
False; cutting hair would change what it looks like but, braiding it keeps it the same substance it is.
Question 18 :
My best guess would either be A or D. I would lean more towards D because if there are different mixtures then it depends on what you are mixing.
Hope it helps in some way. <3
Answer:
A) SiO2 is the limiting reactant
B) Theoretical yield= 72333.3g
C) % yield =91.5%
Explanation:
SiO2(s) + 2C(s) --------------> Si(s) + 2CO(g)
n(SiO2)= 155000/60 = 2583.33 mols
n(C)= 79000/12= 3291.66 mols
a)SiO2 is the limiting reactant
According to the balanced reaction equation,
60g of SiO2 produced 28g of SiO2
155000g of SiO2 will produce 155000×28/60= 72333.3g
Therefore theoretical yield of Si= 72333.3g
% yield= 66200/72333.3×100/1 =91.5%
<u>Answer:</u> Increasing temperature
<u>Explanation:</u>
The Principle of Le Chatelier states that <u>if a system in equilibrium is subjected to a change of conditions, it will move to a new position in order to counteract the effect that disturbed it and recover the state of equilibrium.
</u>
The variation of one or several of the following factors can alter the equilibrium condition in a chemical reaction:
- Temperature
- The pressure
- The volume
- The concentration of reactants or products
In the case of the reaction in the question, <u>the change that moves the balance to the left will be the one that moves it towards the reagents</u>, that is, that favors the production of reagents instead of products.
-
Decreasing the concentration of SO3 and increasing the concentration of SO2 <u>will favor the production of SO3</u>, which is the product of the reaction.
- Decreasing the volume increases the pressure of the system and the balance will move to where there is less number of moles. In the case of the reaction in question, we have 3 moles of molecules in the reactants (1 mole of O2 + 2 moles of SO2) while in the products there are 2 moles of SO3 only, therefore, <u>decreasing the volume will displace the balance to the right</u>, which corresponds to the sense in which there is less number of moles.
The reaction of the question is an exothermic since ΔH <0, therefore in the reaction heat is produced and it can be written in the following way,
2SO2(g) + O2(g) ⇌ 2SO3(g) + heat
- So, if we increase the temperature we will be adding heat to the system, so the balance would move to the left to compensate for the excess heat in the system.
Answer: Option (d) is the correct answer.
Explanation:
As it is known that like dissolves like. So, water being a polar compound is able to dissolve only polar compounds.
Hence, a compound that is ionic or polar in nature will readily dissolve in water. Whereas non-polar compounds will be insoluble in water.
As 
is a non-polar compound. Hence, it is insoluble in water.
On the other hand, 
is a polar compound due to difference in electronegativity of chlorine and carbon atom there will be development of partial charges. Hence, there will be dipole-dipole forces existing between them.
Whereas 
is an ionic compound and it will readily dissociate into ions when dissolved in water. Also, there will be ion-dipole interactions between sodium and nitrate ions.
Hence, will readily dissolve in water.
Thus, we can conclude that the compounds correctly arranged in order of increasing solubility in water are < < .
