I need help with this one guys , anyone can help? The answer must be form( pic)

What is the second most abundant element in stars? A. helium B. iron C. hydrogen D. oxygen

devlian [24]

The abundance of a chemical element is a measure of the occurrence of the element relative to all other elements in a given environment. Abundance is measured in one of three ways: by the mass-fraction (the same as weight fraction); by the mole-fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases); or by the volume-fraction. Volume-fraction is a common abundance measure in mixed gases such as planetary atmospheres, and is similar in value to molecular mole-fraction for gas mixtures at relatively low densities and pressures, and ideal gas mixtures. Most abundance values in this article are given as mass-fractions.

8 0

3 years ago

Nonrenewable energy sources come out of the ground as liquids, gases,

elixir [45]

Answer:

TRUE

Explanation:

Production of Hydrocarbons from Natural Gas is as stated below:

Natural gas liquids include propane, butane, pentane, hexane, and heptane, but not methane and not always ethane, (may include it sometimes.) since these hydrocarbons need refrigeration to be liquefied.

4 0

2 years ago

Question 14 of 32

ser-zykov [4K]

The equilibrium expression for the reaction; C(s) + O₂(g) ------->CO₂(g) is [CO2]/[C] [O2] option C.

<h3>What is the equilibrium expression?</h3>

The equilibrium expression shows how much of the reactants are converted into products. If the equilibrium constant is large and positive, most of the reactants have been converted into products.

Thus, the equilibrium expression for the reaction; C(s) + O₂(g) ------->CO₂(g) is [CO2]/[C] [O2] option C.

Learn more about equilibrium constant:brainly.com/question/10038290

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6 0

2 years ago

What amount of sucrose (C12H22O11) should be added to 5.83 mol water to lower the vapor pressure of water at 50 °C to 72.0 torr?

Triss [41]

Answer:

The amount of sucrose that must be added is 1.66 moles

Explanation:

Colligative property of lowering vapor pressure has this formula:

Vapor pressure of pure solvent (P°) - Vapor pressure of solution = P° . Xm

We have both vapor pressure (pure solvent and solution9, so let's determine the ΔP

ΔP = 92.6 Torr - 72 Torr = 20.6 Torr

Let's add the data in the formula

20.6 Torr = 92.6 Torr . Xm

Xm = Mole fraction of solute → (mol of solute/ mol of solute + mol of solvent)

Mol of solvent = 5.83 mol (data from the problem)

Therefore Xm = 20.6 Torr / 92.6 Torr → 0.222

Let's find out the moles of solute (our unknown value)

0.22 = moles of solute / moles of solute + 5.83 moles of solvent

0.222 (moles of solute + 5.83 moles of solvent) = moles of solute

0.222 moles of solute + 1.29 moles of solvent = moles of solute

1.29 moles of solvent = moles of solute - 0.222 moles of solute

1.29 moles = 0.778 moles of solute

1.29 / 0.778 = moles of solute → 1.66 moles

3 0

3 years ago

What do you think explains why the larger elements are able to form in a supernova explosion? Use evidence from the Supernova 10

lubasha [3.4K]

Larger elements are able to form in a supernova explosion because the star releases very large amounts of energy as well as neutrons, which allows elements heavier than iron to be produced.

<h3>What is Supernova?</h3>

This is referred to the explosion of a star and it resulting in larger elements being formed through a process known as nucleosynthesis and is usually accompanied by an increase in the brightness of the star.

The elements produced are usually larger than elements such as iron and examples include uranium, gold etc.

This is therefore the reason why it was chosen as the most appropriate choice.

Read more about Supernova here brainly.com/question/27492871

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3 0

1 year ago