The dictionary from #2 falls off the table. How much kinetic energy does it have just before it hits the floor?

What is the longest wavelength in the Balmer series? (Hint: the Rydberg constant for Hydrogen is 1.096776×107 1/m, and the Balme

boyakko [2]

<u>Answer:</u> The longest wavelength of light is 656.5 nm

<u>Explanation:</u>

For the longest wavelength, the transition should be from n to n+1, where: n = lower energy level

To calculate the wavelength of light, we use Rydberg's Equation:

$\frac{1}{\lambda}=R_H\left(\frac{1}{n_i^2}-\frac{1}{n_f^2} \right )$

Where,

$\lambda$ = Wavelength of radiation

$R_H$ = Rydberg's Constant = $1.096776\times 10^7m^{-1}$

$n_f$ = Higher energy level = $n_i+1=(2+1)=3$

$n_i$ = Lower energy level = 2 (Balmer series)

Putting the values in above equation, we get:

$\frac{1}{\lambda }=1.096776\times 10^7m^{-1}\left(\frac{1}{2^2}-\frac{1}{3^2} \right )\\\\\lambda =\frac{1}{1.5233\times 10^6m^{-1}}=6.565\times 10^{-7}m$

Converting this into nanometers, we use the conversion factor:

$1m=10^9nm$

So, $6.565\times 10^{-7}m\times (\frac{10^9nm}{1m})=656.5nm$

Hence, the longest wavelength of light is 656.5 nm

4 0

2 years ago

What is the main benefit of this model?

igor_vitrenko [27]

Answer:

letter D.

Explanation:

it shows a pattern for determining the side of lengths of a triangle yeah the triangle had a model and a length

4 0

2 years ago

A rectangular fence is 3 times as long as it is wide. The perimeter is 60ft. Find the dimensions of the fence

Mashutka [201]

Answer:

The length of the fence is 22.5ft and the width of the fence is 7.5ft.

Explanation:

To solve this problem we will turn this question into an equation.

The equation for the perimeter of a rectangle is 2l + 2w = perimeter.

In the question we were given the perimeter so we can go ahead and plug this in.

2l + 2w = 60

In the question we are also told that the fence is 3 times as long as it is wide. This means that 1l = 3w. We can now subsitute l for 3w so that we only have one variable.

2(3w) + 2w = 60

Now we can simply use algebra to solve for w.

6w + 2w = 60

8w = 60

w = 7.5

Now that we know the value of w we can find the value of l since we know 1l = 3w.

l = 3w

l = 3(7.5)

l = 22.5

The length of the fence is 22.5ft and the width of the fence is 7.5ft.

7 0

2 years ago

Which mixture can be classified as a homogeneous mixture?

Reika [66]

Anything can be homogenous as long as you can only see the same type of liquid
think about it like this
orange juice with pulp is Hetero
orange juice with no pulp is homo

3 0

2 years ago

Read 2 more answers

Sort these species into isoelectronic groups. It doesn\'t matter which group goes in which box, so long as the correct species a

OleMash [197]

Answer : The isoelectronic groups are:

$He,Be^{2+},Li^{+}$

$N^{3-},Mg^{2+}$

$S^{2-},Ti^{4+},K^{+}$

Explanation :

Isoelectronic : It is defined as the compound or molecule having the same number of electrons and the same number of electronic structure.

The element is helium. The number of electrons are 2.
The element is beryllium. The number of electrons are 4. The number of electrons in $Be^{2+}$ = 4 - 2 = 2
The element is lithium. The number of electrons are 3. The number of electrons in $Li^{+}$ = 3 - 1 = 2
The element is nitrogen. The number of electrons are 7. The number of electrons in $N^{3-}$ = 7 + 3 = 10
The element is neon. The number of electrons are 10.
The element is sulfur. The number of electrons are 16. The number of electrons in $S^{2-}$ = 16 + 2 = 18
The element is magnesium. The number of electrons are 12. The number of electrons in $Mg^{2+}$ = 12 - 2 = 10
The element is titanium. The number of electrons are 22. The number of electrons in $Ti^{4+}$ = 22 - 4 = 18
The element is potassium. The number of electrons are 19. The number of electrons in $K^{+}$ = 19 - 1 = 18

The isoelectronic groups are:

$He,Be^{2+},Li^{+}$

$N^{3-},Mg^{2+}$

$S^{2-},Ti^{4+},K^{+}$

7 0

2 years ago