<h3><u>Answer;</u></h3>
C) A convex lens has a thick center and thin edges; a concave lens has a thin center and thicker edges.
<h3><u>Explanation;</u></h3>
- Convex lens refers to the lens which merges the light rays at a particular point, that travels through it, while a concave lens can be identified as the lens which disperses the light rays around, that hits the lenses.
- A convex lens is thicker at the center, as compared to its edges, while a concave lens is thinner at the center as compared to its edges.
- A concave lens is thicker at the edges than in the middle and spreads light rays apart producing an image smaller than the actual object. A convex lens on the other hand, is thinner at the edges and thicker towards the center, that is they are bent towards a central point.
1. This is a combustion reaction.<span>
<span>Combustion reactions can happen with the </span>presence of O</span>₂ <span>gas. O₂<span>
reacts with another element or compound and </span></span>oxidize<span> it. Here ethanol reacts with O₂<span> and produces </span></span>CO₂ and H₂O as products.<span> <span>Combustion is also called as </span></span>burning. <span>
2.
Reaction will shift to right. <span>
</span><span>If more CH</span>₃CH₂OH is added to the system, then the</span> amount of CH₃CH₂OH will increase.<span> <span>Then the equilibrium in the system </span></span>will be broken.<span> <span>To make the equilibrium again, the </span></span>added CH₃CH₂OH should be removed.<span> To do that system will consume more CH</span>₃CH₂<span>OH to make products which helps to decrease
the amount of ethanol. Hence,
the reaction will shift to right.<span>
3. The reaction
will shift to right.</span><span>
</span><span>If the water is extracted from the system, the </span>amount of water will decrease. <span>That means the </span>amount of products decrease. Then the system will try to gain equilibrium by increasing the water. To increase water the forward reaction should be enhanced. <span>Hence, the</span> reaction will shift to right.<span>
4. The reaction
will shift to right.
</span><span>This is an </span>exothermic reaction <span>since it </span>produces heat. If the produced heat is removed, then the system will be cold. To maintain the temperature, system has to increase the amount of heat produced. Then, the forward reaction should be
enhanced. Hence, the reaction
will shift to right.<span>
5. The Le
Chatelier's principle.
</span>Le Chatelier's principle says if a
condition changes in a system which was in an equilibrium state, the system
will try to gain equilibrium by correcting the changed condition back to
normal. Most of industries which make
chemicals use this principle</span>
Answer:
11.25moles of CO2
Explanation:
First, let us generate a balanced equation for the reaction of propane to produce CO2. This reaction called Combustion. It is a reaction in which propane burns in air (O2) to produce CO2 and H20. The equation is given below:
C3H8 + 5O2 —> 3CO2 + 4H2O
From the equation,
1mole of C3H8 produced 3moles of CO2.
Therefore, 3.750 moles of C3H8 will produce = 3.750 x 3 = 11.25moles of CO2
Answer : The mass of sodium bromide added should be, 18.3 grams.
Explanation :
Molality : It is defined as the number of moles of solute present in kilograms of solvent.
Formula used :
Solute is, NaBr and solvent is, water.
Given:
Molality of NaBr = 0.565 mol/kg
Molar mass of NaBr = 103 g/mole
Mass of water = 315 g
Now put all the given values in the above formula, we get:
Thus, the mass of sodium bromide added should be, 18.3 grams.
