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ZanzabumX [31]
3 years ago
5

I need help with 17,18,19,& 21

Chemistry
1 answer:
valentinak56 [21]3 years ago
3 0

Answer:

17. tie hair up

wear goggles

18. i don't know

19. you light it on the side of the box

20. it should be orange because that is the safest.

21. you turn down the electricity thing

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Classify the following mixturesin their proper column​
PolarNik [594]

Answer:

homogeneous mixtures: iron,alcohol,zonrox,wine.

heterogeneous mixtures: smoke,batchoy,spaghetti,halo halo,book,clothes.

8 0
3 years ago
Using the Bohr model, determine the energy in joules of the photon produced when an electron in a Li2+ ion moves from the orbit
djverab [1.8K]

Answer:

1.64x10⁻¹⁸ J

Explanation:

By the Bohr model, the electrons surround the nucleus of the atom in shells or levels of energy. Each one has it's energy, and the electron doesn't fall to the nucleus because it can reach another level of energy, and then return to its level.

When the electrons go to another level, it absorbs energy, and then, when return, this energy is released, as a photon (generally as luminous energy). The value of the energy can be calculated by:

E = hc/λ

Where h is the Planck constant (6.626x10⁻³⁴ J.s), c is the light speed (3.00x10⁸ m/s), and λ is the wavelength of the photon.

The wavelength can be calculated by:

1/λ = R*(1/nf² - 1/ni²)

Where R is the Rydberg constant (1.097x10⁷ m⁻¹), nf is the final orbit, and ni the initial orbit. So:

1/λ = 1.097x10⁷ *(1/1² - 1/2²)

1/λ = 8.227x10⁶

λ = 1.215x10⁻⁷ m

So, the energy is:

E = (6.626x10⁻³⁴ * 3.00x10⁸)/(1.215x10⁻⁷)

E = 1.64x10⁻¹⁸ J

3 0
3 years ago
PLEASE ANSWER ASAP FOR 50 POINTS (scroll down to see the pictures for the questions)
sladkih [1.3K]
Absorption occurs when photons from incident light hit atoms and molecules and cause them to vibrate. The more an object's molecules move and vibrate, the hotter it becomes. This heat is then emitted from the object as thermal energy.
8 0
2 years ago
Read 2 more answers
three molecules of oxygen react with four molecules of hydrogen to produce water molecules write a balanced chemical equation
mixer [17]

Answer:

ExpC

H

4

+  

2

O

2

 

→

 

C

O

2

+  

2

H

2

O

This is the balanced reaction equation for the combustion of methane.

Explanation:

The Law of Conservation of Mass basically states that matter can neither be created nor destroyed. As such, we must be able to show this in our chemical reaction equations.

If you look at the equation above, you'll see an arrow that separates the reaction equation into two parts. This represents the direction of the reaction.

To the left of the arrow, we have our reactants.

To the right of the arrow, we have our products.

The quantity of each individual element in the left must equal the quantity of each individual element in the right.

So if you look below, you'll see the unbalanced equation, and I'll try to explain how to balance the reaction.

C

H

4

+  

O

2

 

→

 

C

O

2

+  

H

2

O

Our reactants in this equation are  

C

H

4

and  

O

2

.

Our next step is to break these down into individual atoms.

We have:

1 C atom, 4 H atoms & 2 O atoms.

If you're confused by this, look to see the little number to the bottom right of each element, the subscript, and it tells you how many of each atom are in the molecule. Make sense?

Now we look to the other side of the equation.

Here we see our products are  

C

O

2

+  

H

2

O

Again, we break these down into individual atoms again.

We have:

1 C atom, 2 H atom, 3 O atom

6 0
3 years ago
Which of the following compounds would be expected to have the strongest ionic bonds?
Luba_88 [7]

Answer:

Compound that has the smallest ions with the greatest charge.

Explanation:

4 0
3 years ago
Read 2 more answers
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