An adult mosquitoes lifespan is about 16 days how many minutes is that

What is the frequency of an X-ray that has a wavelength of 1.5 x 10 -9 m? The speed of electromagnetic radiation is 3.0 x 10 8 m

AlexFokin [52]

Answer:

2.0x10¹⁷ Hz is the frequency of the X-ray

Explanation:

We can find the frequency of a wave of energy from the wavelenght and its speed using the formula:

v = λƒ

Where v is speed (For electromagnetic radiation = 3.0x10⁸m/s)

λ is the wavelength in meters = 1.5x10⁻⁹m

And f is the frequency in s⁻¹ = Hz

Replacing:

3.0x10⁸m/s = 1.5x10⁻⁹m*ƒ

3.0x10⁸m/s / 1.5x10⁻⁹m = f

f =

<h3>2.0x10¹⁷ Hz is the frequency of the X-ray</h3>

3 0

2 years ago

The heat of vaporization of a liquid is 84.0 J/g. How many joules of heat would it take to completely vaporize 172 g of this liq

Aliun [14]

Answer:

14,448 J of heat would it take to completely vaporize 172 g of this liquid at its boiling point.

Explanation:

The heat Q that is necessary to provide for a mass m of a certain substance to change phase is equal to Q = m*L, where L is called the latent heat of the substance and depends on the type of phase change.

During the evaporation process, a substance goes from a liquid to a gaseous state and needs to absorb a certain amount of heat from its immediate surroundings, which results in its cooling. The heat absorbed is called the heat of vaporization.

So, it is called "heat of vaporization", the energy required to change 1 gram of substance from a liquid state to a gaseous state at the boiling point.

In this case, being:

Q=?
m= 172 g

L= 84 $\frac{J}{g}$

and replacing in the expression Q = m*L you get:

Q=172 g*84 $\frac{J}{g}$

Q=14,448 J

14,448 J of heat would it take to completely vaporize 172 g of this liquid at its boiling point.

5 0

2 years ago

Lead(II) oxide from an ore can be reduced to elemental lead by heating in a furnace with carbon. Calculate the expected yield of

Lelu [443]

Answer:

53kg is the expected yield of lead

Explanation:

Firstly, in order to solve this question, we need to write the equation of reaction correctly. This is as follows:

PbO(s) + C(s) ---> Pb(l) + CO(g)

We proceed from here. We should get the limiting reactant but this can only be obtained by getting the number of moles of each reactant present.

The formula to use across all boards is that the number of moles is the mass of each of the reactant divided by the molar mass of each of the reactant.

For PBO, mass is 57kg = 57000g

Molar mass of PBO = 223.20g/mol

The number of moles is thus 57,000/223.2 = 255.37 moles

For carbon, mass is also 57kg = 57000g

Molar mass is 12g/mol

Number of moles of carbon = 57000/12 = 4750 moles

From the number of moles, we can see that the number of moles of Carbon is greater than that of PbO. This means that PbO is the limiting reagent.

Hence we use it to calculate percentage yield.

The number of moles of lead formed is the same of number of moles of lead oxide = 255.37 since we have mole ratio of 1 to 1

The molar mass of lead is 207.20g/mol

The mass of lead formed is = moles of lead formed * molar mass of lead = 207.20 * 255.37 = 52,912g which is approximately 53kg

Hence the expected yield is 53kg

6 0

3 years ago

Carbondioxide gas is't collectable in water. why?

Lisa [10]

Answer:

carbon dioxide is a gas so it isn't collected over water.

Explanation:

it works for insoluble gases such as hydrogen,or gases that do not dissolve easily in water such as ammonia and chlorine are readily soluble in water and are not collected this way.

hope it is helpful for you.

4 0

3 years ago

When you decrease the volume of a gas, what happens to the temperature?

ale4655 [162]

the temperature is decreased

4 0

3 years ago