What is the wavelength of a light of frequency 7.21 x 1014 Hz?
O A. 237 nm
B. 721 nm
C. 416 nm
O D. 628 nm

Answer:

Lead

that can be found in the periodic table of elements

Explanation:

Answer:

The correct answer is -

1. Malaysia - Kuala Lumpur 3.1390° N, 101.6869° E

2. Indonesia - Jakarta - 6.2088° S, 106.8456° E

3. Vietnam - Hanoi - 21.0278° N, 105.8342° E

4. Taiwan - Taipei  -25.0330° N, 121.5654° E

5. China - Beijing - 39.9042° N, 116.4074° E

6. Palau - Ngerulmud  - 7.5004° N, 134.6243° E

7. Japan - Tokyo - 35.6762° N, 139.6503° E

Explanation:

The Philippines does not share its land borders with any country, however, the Philippines claims that they share their boundary with Malaysia. Other than land borders they also share maritime borders with Palau, Taiwan, Vietnam,  China, Indonesia, and Japan.

All these neighboring countries have capitals that are as follows with their coordinates on the atlas-

1. Malaysia - Kuala Lumpur 3.1390° N, 101.6869° E

2. Indonesia - Jakarta - 6.2088° S, 106.8456° E

3. Vietnam - Hanoi - 21.0278° N, 105.8342° E

4. Taiwan - Taipei  -25.0330° N, 121.5654° E

5. China - Beijing - 39.9042° N, 116.4074° E

6. Palau - Ngerulmud  - 7.5004° N, 134.6243° E

7. Japan - Tokyo - 35.6762° N, 139.6503° E

Answer:

See Explanation

Explanation:

Given that;

N/No = (1/2)^t/t1/2

Where;

No = amount of radioactive isotope originally present

N = A mount of radioactive isotope present at time t

t = time taken

t1/2 = half life

N/1000=(1/2)^3/6

N/1000=(1/2)^0.5

N = (1/2)^0.5 * 1000

N= 707 unstable nuclei

Since the value of the initial activity of the radioactive material was not given, the activity of the radioactive material after three months is given by;

Decay constant = 0.693/t1/2 = 0.693/6 months = 0.1155 month^-1

Hence;

A=Aoe^-kt

Where;

A = Activity after a time t

Ao = initial activity

k = decay constant

t = time taken

A = Aoe^-3 *0.1155

A=Aoe^-0.3465

Answer:

6

Explanation:i dont know

Answer:

The maximum amount of water vapor the air can hold at a given temperature is known as the Saturation Point, it is also identified as 100% relative humidity.

Answer:

for number of neutrons it is mass number take away the atomic number

number of electron is the same as number of proton unless there is a charge like +2 it will have 2 less electron than the proton (atomic number ) number.

number of proton is the atomic number

Explanation:

hope it make sense:)

Answer:

D. The number or protons

Explanation:

It doesn't matter how many electrons or neutrons an atom has; the element always is defined by its number of protons.

Answer:

a. 686g of H2SO4 are present.

b. 3.321L would be made

Explanation:

a. Molarity, M, is an unit of concentration defined as the ratio between moles of solute (In this case H2SO4) and liters of solution. The moles of H2SO4 in 3.5L of 2.0M H2SO4 are:

3.5L * (2.0mol H2SO4 / L) = 7.0 moles H2SO4

The mass is obtained using molar mass of H2SO4 -98g/mol-:

7.0 moles H2SO4 * (98g / mol) = 686g of H2SO4 are present

b. The density of H2SO4 is 1.83g/mL. The volume of 2.0M H2SO4 per liter of solution is:

2.0mol H2SO4 / L * (98g / mol) * (1mL / 1.83g) = 107mL of H2SO4 are present per liter of solution. In 3L there are:

3L  (107mL / L) = 321mL = 0.321L of H2SO4 must be added to 3L of water to produce 2.0M H2SO4. The total volume is:

3L + 0.321L = 3.321L would be made

Answer:

3.11 is the pH of the buffer

Explanation:

The pH of a buffer is obtained using H-H equation:

pH = pKa + log [Conjugate base] / [Weak acid]

Where pH is the pH of the buffer, pKa = -log Ka = 3.14 for the citric buffer and [] could be taken as the moles of each species.

The citric acid,HX (Weak acid), reacts with NaOH to produce sodium citrate, NaX (weak base) and water:

HX + NaOH → H2O + NaX

That means the moles of NaOH added = Moles of sodium citrate produced

And the resulitng moles of HX = Initial moles - Moles NaOH added

Moles HX and NaX:

Moles NaOH = 0.100L * (0.65mol / L) = 0.065 moles NaOH = Moles NaX

Moles HX = 0.300L * (0.45mol / L) = 0.135 moles HX - 0.065 moles NaOH = 0.070 moles HX

Replacing in H-H equation:

pH = 3.14 + log [0.065mol] / [0.070mol]

pH = 3.11 is the pH of the buffer

Answer:

true

Explanation:

Endo means inside

but exo means outside

an Endo thermic reaction sounds like it wouldn't be the one to give off heat, so it might be storing heat.

Answer:

1.00 m^3

Explanation:

Boyles law says that PV = constant, or P1V1=P2V2, while temperature remains constant.

0.25 m^3 *4 atm = V* 1 atm

V = 0.25 m^3 / (1/4)

= 1 m^3

Answer:

True.

Explanation:

Yes, analyses of enzymes found in the blood are used as indicators of tissue damage in the heart, liver, muscle etc has occurred. This leakage of enzymes into the bloodstream tells us whether the tissue is damaged or not. Lactate dehydrogenase is a type of enzyme which is used as indicator which is responsible for the interconverts lactate and pyruvate. The concentration of this enzyme in the blood tells us about tissue damage.

Answer:

a. True

Explanation:

The co enzyme used for this reaction is NADH+, here H+ acts as co substrate.

This is required to find the tissue damage that has occurred in our body which resulted in leakage of cellular enzymes into the bloodstream.

This coenzyme is used for conversion of lactose dehydrogenase.

Answer:

A. London dispersion

Explanation:

London dispersion force is a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles. 

The intermolecular forces are due to the attraction between temporary dipoles, and their induced temporary dipoles are the type of  London dispersion force. Therefore, option A is correct.

When the electrons in two nearby atoms occupy positions that cause the atoms to temporarily form dipoles, the consequence is the London dispersion force, a transient attractive force. The term "induced dipole-induced dipole attraction" is frequently used to describe this effect.

The electron density of a molecule is redistributed towards another molecule because the electrons in nearby molecules "flee" when they repel one another. This is typically explained as the instantaneous production of attracted dipoles.

The material's atomic or molecular weight affects the London dispersion forces. More electrons and stronger London forces are present in heavier atoms or molecules. They are therefore more difficult to melt or boil.

Thus, option A is correct.

To learn more about london dispersion force, follow the link;

https://brainly.com/question/20514601

#SPJ2

Answer:

XeF4                  True

[PdCl4]2−           True

naphthalene      True

Furan                  False

C4H4O               False  

Explanation:

From the given information:

Only XeF4;  [PdCl4]2−;  naphthalene are true. This is because their molecules contain -nC₂ axis which is perpendicular to the Cn axis. The image attached below shows the structural formula of each compound, there below, we can see that Furan only possesses one C₂ axis but not -nC₂ ⊥ C₂.

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\[/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

[tex]n = \frac{3.01 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{3.01}{6.02} \\ = 0.5[/tex]

We have the final answer as

Hope this helps you

Answer: D it’s is 2.0 s

i think..

Explanation:

Answer:

Percent yield of silver obtained = 78.18% (Approx.)

Explanation:

Given:

Amount of copper = 50 gram

Amount of silver nitrate = 300 gram

Amount of silver = 149 gram

Find:

Percent yield of silver obtained

Computation:

Percentage of Silver in silver nitrate =  108[100/(108+14+48)]

Percentage of Silver in silver nitrate = 108/[100/170]

Percentage of Silver in silver nitrate = 63.53% (Approx.)

Amount of Silver produced = [63.53%][300]

Amount of Silver produced = 190.59 gram

Percent yield of silver obtained = [Amount of silver / Amount of silver produced]100

Percent yield of silver obtained = [149/190.59]100

Percent yield of silver obtained = 78.18% (Approx.)

I believe the answer for this is:

C. Visible Light Rays

I hope this helps! :D

Answer:

C, visible light rays :)

Explanation:

Hope i could help

The question is incomplete, the complete question is:

Nitrogen and fluorine react to form nitrogen fluoride according to the chemical equation:

[tex]N_2(g)+3F_2(g)\rightarrow 2NF_3(g)[/tex]

A sample contains 19.3 g of [tex]N_2[/tex] is reacted with 19.3 g of [tex]F_2[/tex]. Now we need to find the amount of [tex]NF_3[/tex] that can be formed by the complete reactions of each of the reactants.

If all of the [tex]N_2[/tex] was used up in the reaction, how many moles of [tex]NF_3[/tex] would be produced?

Answer: 1.378 moles of [tex]NF_3[/tex] are produced in the reaction.

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]       ......(1)

Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.

Excess reagent is defined as the reagent which is left behind after the completion of the reaction.

In the given chemical reaction, [tex]N_2[/tex] is considered as a limiting reagent because it limits the formation of the product and it was completely consumed in the reaction.

We are given:

Mass of [tex]N_2[/tex] = 19.3 g

Molar mass of [tex]N_2[/tex] = 28.02 g/mol

Putting values in equation 1:

[tex]\text{Moles of }N_2=\frac{19.3g}{28.02g/mol}=0.689mol[/tex]

For the given chemical reaction:

[tex]N_2(g)+3F_2(g)\rightarrow 2NF_3(g)[/tex]

By the stoichiometry of the reaction:

1 mole of [tex]N_2[/tex] produces 2 moles of [tex]NF_3[/tex]

So, 0.689 moles of [tex]N_2[/tex] will produce = [tex]\frac{2}{1}\times 0.689=1.378mol[/tex] of [tex]NF_3[/tex]

Hence, 1.378 moles of [tex]NF_3[/tex] are produced in the reaction.

According to Le cha telier's principle when we increase the pressure of a equilibrium reaction the reaction shift to the side where few moles of gas present.

Your reaction (Notice - I guess the reaction you written is wrong, but still I'm solving with your given prediction)

3NaI (g) + H2 (g) = 2NaHI (g)

Where access of sodium iodide is reacting with Hydrogen gas to form NaHI molecule.

Number of moles of gas on reaction side - 3+2 = 5 moles

Number of moles of gas on product side - 2 moles

Conclusion- the reaction will shift to the right of the reaction

According to Le cha telier's principle when we increase the pressure of a equilibrium reaction the reaction shift to the side where few moles of gas present.

Your reaction (Notice - I guess the reaction you written is wrong, but still I'm solving with your given prediction)

3NaI (g) + H2 (g) = 2NaHI (g)

Where access of sodium iodide is reacting with Hydrogen gas to form NaHI molecule.

Number of moles of gas on reaction side - 3+2 = 5 moles

Number of moles of gas on product side - 2 moles

Conclusion- the reaction will shift to the right of the reaction

Answer:

Evaporation

Explanation:

Water in the ocean, rivers, lakes, etc. is part of the hydrosphere, and when that water evaporates it enters the atmosphere

Answer:

How to Formulate an Effective Research Hypothesis

State the problem that you are trying to solve. Make sure that the hypothesis clearly defines the topic and the focus of the experiment.

Try to write the hypothesis as an if-then statement. ...

Define the variables.

Explanation:

Answer:

Answer C

Explanation:

Got it off of q**zlet ;)

Answer

Its C confirmed

Explanation:

Just did the test

When the concentration of the HCl is varied, the color of the solution is changed as the equilibrium position moves to the left or right.

The term equilibrium in a chemical reaction connotes that the forward and the revers reactions proceed at the same rate. Let us note that Co(H2O)6^2+ is pink in color while  CoCl4^2– is blue in color.

As such, when the concentration of the HCl is varied, the color of the solution is changed as the equilibrium position moves to the left or right.

Learn more anout equilibrium: https://brainly.com/question/365923

Answer:

when rutherford performed his experiment, only 1 in 20,000 alpha particles bounced straight back or were deflected greatly. the rest went straight through the gold foil. e) based on this evidence, what is in atom's center? positively charged particles.

Explanation:

Answer:

148.85 g or 0.14885 kg

Explanation:

Applying,

Heat lost by the metal cube = heat gained by the water.

c'm'(t₁-t₃) = cm(t₃-t₂).................. Equation 1

Where c' = specific heat capacity of the metal, m' = mass of the metal, c = specific heat capacity of water, m = mass of water, t₁ = Initial temperature of the metal, t₂ = Initial temperature of water, t₃ = equilibrium temperature.

make m the subject of the equation

m = c'm'(t₁-t₃)/c(t₃-t₂).............. Equation 2

From the questions,

Given: c' = 0.55 J/g.°C, m' = 55 g, t₁ = 85°C, t₂ = 20°C, t₃ = 23°C

Constant: c = 4.2 J/g.°C

Substitute these values into equation 2

m = 0.55×55×(85-23)/(4.2×[23-20])

m = 1875.5/12.6

m = 148.85 g.

m = 0.14885 kg

Answer:

223.08 K

Explanation:

First we convert 173.0 °C to K:

With the absolute temperature we can use Charles' law to solve this problem:

Where in this case:

We input the data:

And solve for T₂:

Answer:

The heat capacity of the metal underneath the gold is 0.431 J/g°C

Explanation:

Using the formula as outlined in the image:

Q = m × c × ∆T

Where;

Q = amount of heat energy (J)

m = mass of substance (g)

c = specific heat capacity (J/g°C)

∆T = change in temperature (°C)

According to the information in this question;

Q = 503.9J

m = 23.02g

c = ?

∆T = 74°C - 23.2°C = 50.8°C

Using Q = m × c × ∆T

c = Q ÷ m∆T

c = 503.9 ÷ (23.02 × 50.8)

c = 503.9 ÷ 1169.42

c = 0.431 J/g°C

From the above heat capacity of the metal underneath the gold, it is obvious that the metal is not pure gold (c = 0.129J/g°C)

Answer:

shorter waves equal more power

Explanation:

"higher frequency and shorter wavelengths are one in the same thing. the higher frequency - higher energy results from Planck's realization of the quantization of light and resulting E=hf equation"