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3 years ago

Why is the fact that light travels at 300,000 km/s is a consequence of energy conservation?

Chemistry

1 answer:

user100 [1]3 years ago

8 0

Answer is: true.

The law of conservation of energy states that the total energy of an isolated system remains constant; energy can neither be created nor destroyed; it can only be transformed or transferred from one form to another.

Albert Einstein (1879-1955) proposed that a beam of light is a collection of discrete wave packets (photons) with energy hν, where h is Planck constant and ν is frequency.

E = h·ν.

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As ________________ increases, air pressure decreases. A) pollution B) water vapor C) radiation D) altitude

lara [203]

Answer:

d or b

Explanation:

8 0

3 years ago

Why is the composition of the vapor different from the composition of the solution?

BaLLatris [955]

If there is solution with nonvolatile solute (substance that does not readily evaporate into a gas) only the pure vapor of the solvent is present above the solution and solute stays in solution and do not enters vapor above solution. This is because nonvolatile solute has slow rate of evaporation and low vapore pressure.
If solution has two volatile components, composition of the vapor depends on vapor pressures of the components according Raoult's Law.

8 0

3 years ago

Which reactant will be used up first if 78.1g of o2 is reacted with 62.4g of c4h10?

dlinn [17]

Answer:

Reagent O₂ will be consumed first.

Explanation:

The balanced reaction between O₂ and C₄H₁₀ is:

2 C₄H₁₀ + 13 O₂ → 8 CO₂ + 10 H₂O

Then, by reaction stoichiometry, the following amounts of reactants and products participate in the reaction:

C₄H₁₀: 2 moles
O₂: 13 moles
CO₂: 8 moles
H₂O: 10 moles

Being:

C: 12 g/mole
H: 1 g/mole
O: 16 g/mole

The molar mass of the compounds that participate in the reaction is:

C₄H₁₀: 4*12 g/mole + 10*1 g/mole= 58 g/mole
O₂: 2*16 g/mole= 32 g/mole
CO₂: 12 g/mole + 2*16 g/mole= 44 g/mole
H₂O: 2*1 g/mole + 16 g/mole= 18 g/mole

Then, by reaction stoichiometry, the following mass quantities of reactants and products participate in the reaction:

C₄H₁₀: 2 moles* 58 g/mole= 116 g
O₂: 13 moles* 32 g/mole= 416 g
CO₂: 8 moles* 44 g/mole= 352 g
H₂O: 10 moles* 18 g/mole= 180 g

If 78.1 g of O₂ react, it is possible to apply the following rule of three: if by stoichiometry 416 g of O₂ react with 116 g of C₄H₁₀, 62.4 g of C₄H₁₀ with how much mass of O₂ do they react?

$mass of O_{2} =\frac{416grams of O_{2}*62.4 grams ofC_{4}H_{10} }{116 grams of C_{4}H_{10}}$

mass of O₂= 223.78 grams

But 21.78 grams of O₂ are not available, 78.1 grams are available. Since you have less mass than you need to react with 62.4 g of C₄H₁₀, reagent O₂ will be consumed first.

3 0

3 years ago

What is the salt produced when calcium hydroxide, Ca(OH)2, reacts with phosphoric acid, H3PO4, in a neutralization reaction?

Alecsey [184]

It's a double replacement reaction, so
3 Ca(OH)2 + 2 H3PO4 --> Ca3(PO4)2 + 6 H2O

Ca3(PO4)2

6 0

3 years ago

We can’t see the dark side of the moon from earth because

choli [55]

On the Moon, there is (as on Earth) day and night (though the day is as long as month onEarth) and no spot remains dark for longer (except for the pole caps as on Earth). There is, of course, the far side of the Moon, most of which is invisible from Earth.

3 0

3 years ago