All categories

3 years ago

The earth formed 4600 million years ago. What percentage of the Earth’s age has the atmosphere been its current composition

Chemistry

1 answer:

nata0808 [166]3 years ago

4 0

Answer: 4.35%

Explanation:

Scientists estimate that the current composition of gases in the Earth's atmosphere has been stable for the last 200 million years or so.

If the Earth was formed 4,600 million years ago then the percentage of her age that the atmosphere has been in its composition is:

= 200 / 4,600 * 100%

= 4.35%

You might be interested in

How much of a sample remains after three half-lives have occurred? 1/16 of the original sample 1/9 of the original sample 1/8 of

Drupady [299]

For this question, assume that you have 1 compound. This compound is divided in half once, so you are left with 0.5. That 0.5 that remains is divided in half again, this is the second half-life, and you are left with 0.25. The final half life involves dividing 0.25 in half, which means you are left with 0.125. For the answer to make sense, you need to know your conversions between decimals and fractions. To make it simple, if you have 0.125 and you times it by 8, you are left with your initial value of 1. Therefore, after three half-lives, you are left with 1/8th of the compound.

5 0

3 years ago

Read 2 more answers

The high polarity of the oxygen-carbon bond in alcohols is what allows them to be soluble in water.

Anna11 [10]

This is false. An alcohol does indeed have a polar C-O single bond, but what we should really be focusing on is the extraordinarily polar O-H single bond. When oxygen, fluorine, or nitrogen is bound to a hydrogen atom, there is a small (but not negligible) charge separation, where the eletronegative N, O, or F has a partial negative charge, and the H has a partial positive charge. Water has two O-H single bonds in it (structure is H-O-H). The partially negative charge on the O of the water molecule (specifically around the lone pair) can become attracted either a neighboring water molecule's partially positive H atom, or an alcohol's partially positive H atom. This is weak (and partially covalent) attraction is called a hydrogen bond. This is stronger than a typical dipole-dipole attraction (as would be seen between neighboring C-O single bonds), and much stronger than dispersion forces (between any two atoms). When the solvent (water) and the solute (the alcohol) both exhibit similar intermolecular forces (hydrogen bonding being the most important in this case), they can mix completely in all proportions (i.e. they are miscible) in water.

8 0

3 years ago

Gaseous methane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water. If 2.59 g of water is produc

max2010maxim [7]

<u>Answer:</u> The percent yield of the water is 31.98 %

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

<u>For methane:</u>

Given mass of methane = 6.58 g

Molar mass of methane = 16 g/mol

Putting values in equation 1, we get:

$\text{Moles of methane}=\frac{6.58g}{16g/mol}=0.411mol$

<u>For oxygen gas:</u>

Given mass of oxygen gas = 14.4 g

Molar mass of oxygen gas = 32 g/mol

Putting values in equation 1, we get:

$\text{Moles of oxygen gas}=\frac{14.4g}{32g/mol}=0.45mol$

The chemical equation for the combustion of methane is:

$CH_4+2O_2\rightarrow CO_2+2H_2O$

By Stoichiometry of the reaction:

2 moles of oxygen gas reacts with 1 mole of methane

So, 0.45 moles of oxygen gas will react with = $\frac{1}{2}\times 0.45=0.225mol$ of methane

As, given amount of methane is more than the required amount. So, it is considered as an excess reagent.

Thus, oxygen gas is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction

2 moles of oxygen gas produces 2 moles of water

So, 0.45 moles of oxygen gas will produce = $\frac{2}{2}\times 0.45=0.45$ moles of water

Now, calculating the mass of water from equation 1, we get:

Molar mass of water = 18 g/mol

Moles of water = 0.45 moles

Putting values in equation 1, we get:

$0.45mol=\frac{\text{Mass of water}}{18g/mol}\\\\\text{Mass of water}=(0.45mol\times 18g/mol)=8.1g$

To calculate the percentage yield of water, we use the equation:

$\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100$

Experimental yield of water = 2.59 g

Theoretical yield of water = 8.1 g

Putting values in above equation, we get:

$\%\text{ yield of water}=\frac{2.59g}{8.1g}\times 100\\\\\% \text{yield of water}=31.98\%$

Hence, the percent yield of the water is 31.98 %

4 0

3 years ago

What do the sweat collection pads tell the scientist?

spayn [35]

A
Is the correct answer

I’m 95% sure

4 0

3 years ago

Read 2 more answers

Calculate the speed of light in an unknown substance whose index of refraction is 1.65. Would you expect the light to bend towar

Anna71 [15]

(a) The speed of light in the unknown substance is determined 1.82 x 10⁸ m/s.

(b) The light will bend away from the normal since speed of light in air is not equal to speed of light in the substance.

<h3>What is the speed of light?</h3>

The speed of light passing from air into the substance is calculated as follows;

refractive index = speed of light in air / speed of light in the substance

speed of light in the substance = speed of light in air/refractive index

speed of light in the substance = (3 x 10⁸) / (1.65)

speed of light in the substance = 1.82 x 10⁸ m/s

Thus, the light will bend away from the normal since speed of light in air is not equal to speed of light in the substance.

Learn more about speed of light here: brainly.com/question/104425

#SPJ1

8 0

2 years ago