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2 years ago

Explain why the law of conservation of energy can mean that we do not have unlimited sources of energy.

1 answer:

5 0

<span>The law of conservation of energy states that energy can neither be created nor destroyed - it can only be converted from one form to another. It basically means that energy can't just appear, but has to be converted from existing energy; for example, the chemical energy in petrol is turned into electrical energy to power a car.Remember the total energy of universe is constant,,and no more energy can be drawn from out if we collect all universe's energy at a single point(its the big bang energy splitted during </span>

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Diethyl ether is produced from ethanol according to the following equation:

juin [17]

The balanced chemical equation is given as:

2CH3CH2OH(l) → CH3CH2OCH2CH3(l) + H2O(l)

We are given the yield of CH3CH2OCH2CH3 and the amount of ethanol to be used for the reaction. These values will be the starting point for the calculations.

Theoretical amount of product produced:
329 g CH3CH2OH ( 1 mol / 46.07 g ) ( 1 mol CH3CH2OCH2CH3 / 2 mol CH3CH2OH ) (74.12 g / mol ) = 264.66 g CH3CH2OCH2CH3

% yield = .775 = actual yield / 264.66

actual yield = 205.11 g CH3CH2OCH2CH3

6 0

2 years ago

What is the thinnest type of crust?

Trava [24]

The correct answer is oceanic crust, 80 km, Hope this helps let me know.

8 0

3 years ago

For the following systems at equilibrium C: CaCO3(s) ⇌ CaO(s)+CO2(g) ΔH=+178 kJ/mol D: PCl3(g)+Cl2(g) ⇌ PCl5(g) ΔH=−88 kJ/mol cl

Rama09 [41]

Explanation:

C: $CaCO_3(s)\rightleftharpoons CaO(s)+CO_2(g)$ ΔH=+178 kJ/mol

For an endothermic reaction, heat is getting absorbed during a chemical reaction and is written on the reactant side.

$A+\text{heat}\rightleftharpoons B$

Any change in the equilibrium is studied on the basis of Le-Chatelier's principle. This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

Treat heat as a reactant and on increasing a reactant at equilibrium, shifts the reaction in the forward direction.

Increase temperature → increase in heat → forward direction

Decrease temperature → decease in heat → backward direction

System C - Increase temperature : Reaction will move forward

System C - Decrease temperature : Reaction will move backward

D: $PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$ ΔH=−88 kJ/mol

The total enthalpy of the reaction comes out to be negative .

The temperature of the surrounding will increase.

For an exothermic reaction, heat is released during a chemical reaction and is written on the product side.

$A\rightleftharpoons B+\text{ heat}$

Treat heat as a product and on increasing a product at equilibrium, shifts the reaction in the backward direction.

Increase temperature → increase in heat → backward direction

Decrease temperature → decease in heat → forward direction

System D - Increase temperature : Reaction will move backward

System D - Decrease temperature : Reaction will move forward

7 0

2 years ago

3) During the day at 27°C a cylinder with a sliding top contains 20.0 liters

tatiyna

Answer:

$T_2=12\°C$

Explanation:

Hello there!

In this case, according to the Charles' law equation which help us to understand the directly proportional relationship between volume and temperature:

$\frac{T_2}{V_2}=\frac{T_1}{V_1}$

Thus, by solving for the final temperature, T2, and making sure we use the temperatures in Kelvin, we can calculate the final temperature as shown below:

$T_2=\frac{T_1V_2}{V_1} \\\\T_2=\frac{(27+273)K*19L}{20.0L}\\\\T_2=285-273\\\\T_2=12\°C$

Best regards!

4 0

2 years ago

What describes a change that occurs when one substance reacts to another substance?

Slav-nsk [51]

A chemical or physical change

8 0

3 years ago