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3 years ago

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explain why the sun appers to be the brightest star in the sky. relate your explanation with an example such as street lights. t

his is science

1 answer:

Zarrin [17]3 years ago

7 0

Answer:

The sun is a star but It is the brightest in the sky because it is the closest star to earth.

I don't know how to compare it to street lights though...

Explanation:

You might be interested in

Propane can be turned into hydrogen by the two-step reforming process. In the first step, propane and water react to form carbon

Liono4ka [1.6K]

Answer: The net chemical reaction:

$C_3H_8(g)+6H2_O(g)\rightarrow 10H_2(g)+3CO_2(g)$

Explanation:

Step 1 : Propane reacts with water to form carbon monoxide and hydrogen gas

$C_3H_8(g)+3 H_2O(g)\rightarrow 3 CO(g)+7 H_2(g)$ ...[1]

Step 2 : carbon monoxide formed in above step reacts with water tio form hydrogen gas and carbon dioxide.

$CO(g)+H_2O(g)\rightarrow H_2(g)+CO_2(g)$ ...[2]

On Adding [1] and 3 × [2] we get overall balanced chemical reaction for the production of hydrogen from propane and water:

$C_3H_8(g)+6H_2O(g)\rightarrow 10H_2(g)+3CO_2(g)$

1 mole of propane reacts with 6 moles of water vapor to gve 10 moles of hydrogen gas and 3 moles of carbon dioxide.

4 0

4 years ago

A sample of 6.44 g of napthalene (C10H8) is dissolved in 80.1 g of benzene (C6H6). Calculate the percent by mass of napthalene i

Lemur [1.5K]

Answer:

7.44%

Explanation:

$\frac{6.44}{6.44+80.1} *100=7.44$

5 0

3 years ago

Why do transitioning electrons release or absorb energy?

Tom [10]

Answer:

when an electron jumped into higher energy level from lower energy level it must absorbed the energy because with small amount of energy it can not jumped into higher energy level.

when it came back to lower energy level it release extra energy.

Explanation:

The electron is jumped into higher level and back into lower level by absorbing and releasing the energy.

The process is called excitation and de-excitation.

Excitation:

When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits. For example if electron jumped from K to L it must absorbed the energy which is equal the energy difference of these two level. The excited electron thus move back to lower energy level which is K by releasing the energy because electron can not stay longer in higher energy level and comes to ground state.

De-excitation:

When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. this energy is exactly equal to the energy difference between the orbits. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum .

6 0

4 years ago

Read 2 more answers

Sarah measures out 151 grams of SO2. How many moles is this? Express your answer to three significant figures.

Anna11 [10]

Answer:

$\boxed {\boxed {\sf 2.36 \ mol \ SO_2}}$

Explanation:

We are asked to convert grams to moles. We will use the molar mass and dimensional analysis to perform this conversion.

<h3>1. Molar Mass</h3>

The molar mass is the mass of 1 mole of a substance. These values are found on the Periodic Table because they are equivalent to the atomic masses, but the units are grams per mole instead.

We are given a mass of sulfur dioxide (SO₂). Look up the molar masses of the individual elements.

Sulfur (S): 32.07 g/mol
Oxygen (O): 15.999 g/mol

Notice that the formula of the compound contains a subscript. The subscript after O means there are 2 moles of oxygen in 1 mole of sulfur dioxide. We must multiply oxygen's molar mass before adding sulfur's.

O₂: 15.999 * 2 = 31.998 g/mol
SO₂= 32.07 + 31.998 = 64.068 g/mol

<h3>2. Convert Grams to Moles </h3>

Now we will use dimensional analysis to convert grams to moles. From the molar mass, we know there are 64.068 grams of sulfur dioxide per mole, so we can set up a ratio.

$\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}$

We are converting 151 grams to moles, so we multiply by this value.

$151 \ g \ SO_2 *\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}$

Flip the ratio so the units of grams of sulfur dioxide cancel.

$151 \ g \ SO_2 *\frac {1 \ mol \ SO_2}{64.068 \ g \ SO_2}$

$151 *\frac {1 \ mol \ SO_2}{64.068 }$

$\frac {151}{64.068 } \ mol \ SO_2$

$2.356870825 \ mol \ SO_2$

<h3>3. Round </h3>

The original measurement of grams (151) has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place. The 6 in the thousandth place tells us to round the 5 in the hundredth up to a 6.

$2.36 \ mol \ SO_2$

151 grams of sulfur dioxide is approximately <u>2.36 moles of sulfur dioxide.</u>

8 0

3 years ago

What is the element name for 2,5

Nataly_w [17]

Answer:

I think it's vanadium

Explanation:

Hope this helps

4 0

3 years ago