I need help on this question

Answer:

55×10^-26 J

Explanation:

We can calculate the energy of the wave from

E= hc/λ

Where

h= Planks constant = 6.6×10^-34 Is

c= speed of light = 3×10^8 ms-1

λ= wavelength of the wave = 0.36 metres

Recall that cell phone use radio waves which belong to the electromagnetic spectrum hence it must possess the speed of light.

E= 6.6×10^-34 × 3×10^8/ 0.36

E= 55×10^-26 J

Hence the energy possessed by 0.36 meters wavelength radio waves is 55×10^-26 J

Answer:

kii

Explanation:

Answer:

Heat energy (Q) = 1.9925 KJ = 2 KJ (Approx)

Explanation:

Given:

Mass of copper (M) = 45 gram

Change in temperature (ΔT) = 71°C - 12°C = 59°C

Specific heat (c) =0.75 j /g*c

Find:

Heat energy (Q) = ?

Computation:

Heat energy (Q) = Mass(M) × Change in temperature (ΔT) × Specific heat (c)

Heat energy (Q) = 45 gram × 59°C × 0.75 j /g*c

Heat energy (Q) = 1991.25 J

Heat energy (Q) = 1.9925 KJ = 2 KJ (Approx)

Answer:

Explanation:

Soap breaks up the oil into smaller drops, which can mix with the water. It works because soap is made up of molecules with two very different ends. One end of soap molecules love water - they are hydrophilic. The other end of soap molecues hate water - they are hydrophobic.

Answer:

C. Its polar end mixes with the water so it can be washed away.

Explanation:

Just took test

Answer:

4.92 L

Explanation:

Rearrange ideal gas law and solve.

Change C to K.

- Hope that helps! Please let me know if you need further explanation.

Answer:

V = 513.36m/s

Explanation:

Temperature (T) = 25°C = (25 + 273.15) = 298.15K

Speed (V) = 1.92*10³m/s

According to kinetic theory of gases, the speed (v) of a molecule is

V= √(3RT / M)

V = speed or velocity

R = ideal gas constant = 0.082J/mol.K

T = temperature of the gas

M = molar mass

Molar mass of hydrogen molecule = 2.0g/mol

Molar mass of Nitrogen molecule = (2×14.0) = 28.0g/mol

Since they're in the same temperature

V1 / V2 = √(M2 / M1)

1.92×10³ / V2 = √(28 / 2)

1.92×10³ / V2 = √(14)

1.92*10³ / V2 = 3.74

1.92*10³ = 3.74V2

V2 = 1920 / 3.74

V2 = 513.36m/s

The velocity of Nitrogen molecule is 513.36m/s

Answer:

hydrogen

Explanation:

sound energy, kinetic energy,

i cant think of any more but hope this helps

Answer:

Mechanical to kinetic to sound to heat

Explanation:

Remember that all types of energy transformation end in heat

Answer:

jeez thats some calculus stuff right there im pretty sure its b

Explanation:

Answer:

[tex]\large \boxed{\text{0.44 g}}[/tex]  

Explanation:

1. Calculate the molar mass of ammonia

1  N = 1 × 14.01    g = 14.01    g

3 H = 3 ×  1.008 g =  3.024     

                   TOTAL = 17.03   g

2. Calculate the mass of hydrogen

So, there are 3.024 g of H in17.03 g of NH₃.

The conversion factor is either

[tex]\dfrac{\text{3.024 g H}}{\text{17.03 g NH}_{3}} \text{ or } \dfrac{\text{17.03 g NH}_{3}}{\text{3.024 g H}}[/tex]

We want to find grams of H, so we choose the one with grams of H on top.

[tex]\text{Mass of H} = \text{2.5 g NH}_{3} \times \dfrac{\text{3.024 g H}}{\text{17.03 g NH}_{3}} = \textbf{0.44 g H}\\\\\text{The mass of H is $\large \boxed{\textbf{0.44 g}}$}[/tex]

Answer:

Should be A

Explanation:

Answer:

2.078x10^24

Explanation:

No. of atoms of chlorine = 3.45 x 6.022x 10 ^23 x 1

= 2.078x10^24

( to find no. of atoms of, heres the formula i was taught No. of atoms = no. of moles x Avogadros constant x no. of atoms in the formula of compound)

Answer:

A continuous spectrum is a record formed by collecting light of all frequencies traveling through space together. ... A line spectrum is a record formed by collecting light emitted from excited atoms whose electrons are falling back down to lower energy states.

Explanation:

Answer:

increases

Explanation:

As the temperature of a fixed volume of a gas increases, the pressure will increase.

According to this law at constant volume of gas, pressure is directly proportional to the temperature of the gas and it is represented as:

P ∝ T.

It means that if pressure increases then temperature is also increases or if pressure decreases then temperature will also decreases.

So, pressure of the gas increases.

To know more about Gay Lussac's law, visit the below link:
https://brainly.com/question/24002551

The biggest disadvantage of using nuclear power to produce electricity is the nuclear waste must be safely stored for many years.

Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from:

Nuclear reactions produces high amount of energy and many waste materials which are non degradable and will stay in the environment for the long time.

Hence, nuclear waste must be safely stored for many years.

To know more about nuclear power, visit the below link:

https://brainly.com/question/11963586

#SPJ2

Answer:

True!

Explanation:

Fossil fuels are carbon based compounds present deep in the earth left millions of years ago.

hope it helps!

Answer:

B the density stays the same

Answer:

0.03

Explanation:

22.8 g Ba(OH)2 (1 mol Ba (OH)2/ 171.34 g) = 0.133 mol Ba (OH)2

77.2 g H2O (1 mol H2O/18 g) = 4.29 mol H2O

X= molar fraction= mol Ba(OH)2/ mol total

X= 0.133/ (0.133+4.29) = 0.03

0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.

The ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components.

Moles of [tex]Ba(OH)_2[/tex]

Moles = [tex]\frac{mass}{molar \;mass}[/tex]

Moles = [tex]\frac{22.8 g Ba(OH)_2}{171.34 g}[/tex]

= 0.133 mol [tex]Ba (OH)_2[/tex]

Moles of [tex]H_2O[/tex]

[tex]Moles = \frac{mass}{molar \;mass}[/tex]

[tex]Moles = \frac{77.2 g H_2O}{18 g}[/tex]

= 4.29 mol [tex]H_2O[/tex]

The mole fraction of [tex]Ba(OH)_2[/tex]

[tex]\frac{mol Ba(OH)_2}{total \;mol}[/tex]

= 0.03

0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.

Learn more about the mole fraction here:

https://brainly.com/question/8076655

#SPJ2

Answer:

Evaporation

Explanation:

Evaporation turns liquid water into a gas called water vapor. If heat is taken away from water vapor, it condenses. Condensation turns water vapor into a liquid. If heat is taken away from liquid water, it freezes to become ice.

Answer:

D

Explanation:

"Typical nonmetals have a dull, coloured or colourless appearance; are brittle when solid; are poor conductors of heat and electricity; and have acidic oxides." - Wikipedia

Answer:

2.888mm needs for the reaction

Answer:

Gamma Rays.

Explanation:

Gamma-ray photons have the highest energy in the EMR spectrum and their waves have the shortest wavelength.

Answer:

b

Explanation:

Answer: 16700 Joules

Explanation:

The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

[tex]Q=m\times c\times \Delta T[/tex]

Q = Heat absorbed = ?

m = mass of sand = 2 kg

c = heat capacity = [tex]835J/kg^0C[/tex]

Initial temperature  = [tex]T_i[/tex] = [tex]40^0C[/tex]

Final temperature= [tex]T_f[/tex]  = [tex]50^0C[/tex]

Change in temperature ,[tex]\Delta T=T_f-T_i=(50-40)^0C=10^0C[/tex]

Putting in the values, we get:

[tex]Q=2kg\times 835J/kg^0C\times 10^0C[/tex]

[tex]Q=16700J[/tex]

16700 J of energy must be added to a 2-kilogram pile of it to increase its temperature from 40°C to 50°C

Answer: Volume =  50.0 mL in liters : 50.0 / 1000 = 0.05 L

n = M x V

n = 0.20 x 0.05

n = 0.01 moles of solute

Explanation:

The number of moles of solute are present in 50.0 mL of 0.20 M of KNO₃ solution is 0.01 moles.

Moles will be calculated by using the molarity formula because molarity is define as the no. of moles of solute present in per liter of the solution as:

M = n/V, where

M = molarity of KNO₃ = 0.2 M

V = volume of solution = 50mL = 0.05L

Moles will be calculated as:

n = (0.2)(0.05) = 0.01 moles

Hence required moles are 0.01 moles.

To know more about molarity, visit the below link:
https://brainly.com/question/26528084

Answer: The reaction of one mole of oxygen [tex](O_2)[/tex] releases 445 kJ of energy.

Explanation:

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and [tex]\Delta H[/tex] for the reaction comes out to be negative.

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and [tex]\Delta H[/tex] for the reaction comes out to be positive.

[tex]CH_4(g)+2O_2(g)\rightarrow CO_2(g)+2H_2O(l)[/tex]  [tex]\Delta H=-890kJ[/tex]

on halving the reaction, enthalpy also becomes half

[tex]\frac{1}{2}CH_4(g)+O_2(g)\rightarrow \frac{1}{2}CO_2(g)+H_2O(l)[/tex]  [tex]\Delta H=-445kJ[/tex]

Thus The reaction of one mole of oxygen [tex](O_2)[/tex] releases 445 kJ of energy.

Answer:98g/mol

Explanation: