12-How many elements are in the mixture pictured below?
A-7
O B-4
C-3
D-2

Answer:

50%

Explanation:

Let assume that there are:

"a" moles of CH4 & "b" moles of C2H2

Then by applying the ideal gas equation:

PV = nRT

[tex]16.8 \times 10^3 \times V = (a+b)RT[/tex]

Make (a+b) the subject of the formula:

[tex](a+b) = \dfrac{16800 \ V }{RT} mol[/tex] --- (1)

Since 1 mole of CH₄ yields 1 mol of CO₂ & 1 mol of C₂H₂ yields 2 moles of CO₂

Then;

the total moles of CO₂ = (a +2b)

Now:

[tex]25.3 \times 10^3 \times V = (a+ 2b)RT[/tex]

[tex](a + 2b) = \dfrac{25200 \ V}{RT \ mol}[/tex]    ---- (2)

∴

By solving the above equations

[tex]a = \dfrac{8400 \ V}{RT} \\ \\ b = \dfrac{8400 \ V}{RT}[/tex]

Hence, the estimate of the percentage of methane in the original mixture is:

[tex]= 100 \times \dfrac{a}{(a+b)}[/tex]

[tex]= 100 \times \dfrac{8400\dfrac{ \ V}{RT} }{8400\dfrac{ \ V}{RT} + 8400\dfrac{ \ V}{RT}}[/tex]

= 50%

Answer:

[tex]4.86\times10^{-7}\ \text{m}[/tex]

Explanation:

R = Rydberg constant = [tex]1.09677583\times 10^7\ \text{m}^{-1}[/tex]

[tex]n_1[/tex] = Principal quantum number of an energy level = 2

[tex]n_2[/tex] = Principal quantum number of an energy level for the atomic electron transition = 4

Wavelength is given by the Rydberg formula

[tex]\lambda^{-1}=R\left(\dfrac{1}{n_1^2}-\dfrac{1}{n_2^2}\right)\\\Rightarrow \lambda^{-1}=1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\\\Rightarrow \lambda=\left(1.09677583\times 10^7\left(\dfrac{1}{2^2}-\dfrac{1}{4^2}\right)\right)^{-1}\\\Rightarrow \lambda=4.86\times10^{-7}\ \text{m}[/tex]

The wavelength of the light emitted is [tex]4.86\times10^{-7}\ \text{m}[/tex].

Answer:

C Group 11

Explanation:

Group 11, by modern IUPAC numbering, is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), and gold (Au).

These elements show highest electrical conductivity.

Answer:

C Group 11

Explanation:

Group 11, by modern IUPAC numbering, is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), and gold (Au).

These elements show highest electrical conductivity.

Explanation:

true  becouse i sed so                                            

Explanation:

Tidal range is the difference of the mean high tide level and the mean low tide level.

=> Tide range = 0.66m - (-0.55m) = 1.21m.

Answer:

Tidal Change=0.66-(-0.55)=0.66+0.55 = 1.21 meters

Explanation:

Tidal Change is the change in the mean high tide level and mean low tide level.

Tidal Change(m) =High tide level(m) - Low tide level(m)

Answer:

Electronegativity is probably the biggest thing that plays into reactivity. Therefore, since fluorine has a higher electronegativity than chlorine, fluorine is more reactive.

Explanation:

I got it right

Answer:

0.670 mol

Explanation:

Step 1: Write the balanced reaction for the decomposition of alumina

2 Al₂O₃ ⇒ 4 Al + 3 O₂

Step 2: Calculate the moles corresponding to 34.2 g of Al₂O₃

The molar mass of Al₂O₃ is 101.96 g/mol.

34.2 g × 1 mol/101.96 g = 0.335 mol

Step 3: Calculate the moles of Al produced from 0.335 moles of Al₂O₃

The molar ratio of Al₂O₃ to Al is 2:4.

0.335 mol Al₂O₃ × (4 mol Al/2 mol Al₂O₃) = 0.670 mol Al

Answer:

A. p → ~q

Explanation:

I am double checking.

Answer:

Specific heat capacity formula

Explanation:

The heat capacity gives the exact heat energy at which a given mass of a substance is heated from one temperature to another.

This formula can help determine how much heat is gained or lost during the reaction and is given by:

Q = mcΔT

where:

Q = heat energy in Joules or Calories

m - mass of the substance (g)

c = Specific heat capacity (J/kg°C)

ΔT = change in temperature = (final temp - initial temp) (°C)

I hope this was helpful.

Answer:

Because the compound has a formula of M2O, the number of valence electrons of M should be 1. Therefore, (1) Group 1 is the correct answer because elements in group 1 have 1 valence electron.

Explanation:

Answer:

5.44 moles of nitrogen required.

Explanation:

Given data:

Number of moles of NH₃ = 10.88 mol

Moles of N₂ required = ?

Solution:

Chemical equation:

N₂ +  3H₂         →       2NH₃

Now we will compare the moles nitrogen and hydrogen.

               NH₃          :           N₂

                 2             :           1

               10.88        :         1/2×10.88 = 5.44mol

5.44 moles of nitrogen required.

Answer:

m=621.54g

Explanation:

number of moles= mass of H2O/molar mass of H2O

n=m/mm

make mass the subject of the formula

m=n*mm

find molar mass of water

H2O=1(16)+2(1)

mm= 18.0g/mol. n=34.53mol

hence, m=34.53mol*18.0g/mol

m=621.54g

Answer:

Neutrons

Explanation:

Subatomic particles are components atoms, and they include protons, electrons and neutrons. In different isotopes of an atom, the number of neutrons that the atom contains is what changes.

I hope this helps!

Answer:

True? The don't stay exactly still i dont think, but i'd say true.

Explanation:

Answer:

TRUE

Explanation:

In a solid, atoms are packed tightly together and move very slowly. In fact, they do not flow at all: they simply vibrate back and forth.

Key words vibrate, not movement.

Correct me if I'm wrong of course

Answer:

0.0344 moles and 1.93g.

Explanation:

Molarity is defined as the ratio between moles of a solute (In this case, KOH), and the volume. With molarity and volume we can solve the moles of solute. With moles of solute we can find mass of the solute as follows:

Moles KOH:

15.2mL = 0.0152L * (2.26mol / L) = 0.0344moles

Mass KOH:

0.0344 moles * (56.11g/mol) = 1.93g of KOH

Answer:

Hydrogen chloride (HCl) and Calcium hydroxide (CaOH). (see balanced equation below)

Explanation:

In a neutralization reaction as is the case of the question (see attachment), an acid would be neutralized by a base to form salt and water.

The most plausible reactants for the reaction given the number of moles of the product, is therefore Hydrogen chloride (HCl) and Calcium hydroxide (Ca(OH)2).

[tex]HCl _{(aq)} + Ca(OH)_{2} _{(aq)}[/tex] →[tex]CaCl_{2}_{(s)} + H_{2} O_{(l)}[/tex]

Let me know if this was helpful.

Answer:

[tex]PNCl_2[/tex]

Explanation:

Hello!

In this case, when determining empirical formulas by knowing the by-mass percent, we first must assume the percentages as masses so we can compute the moles of each element:

[tex]n_P=\frac{26.73g}{30.97g/mol}=0.863mol\\\\n_N=\frac{12.09g}{14.01g/mol}=0.863mol\\\\n_C_l=\frac{61.18g}{35.45g/mol}=1.726mol[/tex]

Now, for the determination of the subscript of each element in the empirical formula, we divide the moles by the fewest moles (P or N):

[tex]P=\frac{0.863mol}{0.863mol}=1\\\\N= \frac{0.863mol}{0.863mol}=1\\\\Cl=\frac{1.726mol}{0.863mol}2[/tex]

Thus, the empirical formula is:

[tex]PNCl_2[/tex]

Regards!

Answer:

Grass

Oak tree

Explanation:

Bear and human are definitely not and fungus are decomposers.

Answer:

SO SORRY it took so long but the answer is B :)

Explanation:

Trust me and good luck :)

The theory that the planets move around the sun was endorsed by Aristarchus, Copernicus, as well as Galileo. The solar system revolves around the sun.

Aristarchus of Samos was just a Greek astronomer that suggested the very first heliocentric model of the cosmos, wherein the sun, rather than the earth, was even at its center. Despite the fact that his hypothesis was acknowledged by other philosophers of the time, it was dismissed as unrealistic, and the geocentric model remained in use for the next 1,700 years.

Copernicus was also the first to assert that the Earth as well as the other planets orbit the sun. It was really a significant shift in thinking.

Sun can be considered as a star in solar system.

The theory that the planets move around the sun was endorsed by Aristarchus, Copernicus, as well as Galileo. The solar system revolves around the sun.

Therefore, the correct answer will be option (b).

To know more about Aristarchus and Copernicus

https://brainly.com/question/12401405#SPJ2

Answer:

B) Synthesis reaction

Explanation:

synthesis reactions because they take apart larger molecules or compounds

Hope that helps

Answer:

None have backbones

No cell walls

Multicellular

Includes radial or bilateral body symmetry.

Explanation:

Answer:

It's false

Explanation:

Mixtures are always combinations of the same compounds that are at different states.

Answer:

36 electrons

Explanation:

The # of protons is always equal to the atomic number. In the case of Sr (Strontium), it is 38 protons.

The 2+ at the end means that it has a charge of +2, meaning that it LOST two electrons to become a cation with a full valence shell. So, 38 - 2 = 36 electrons

Answer:

38 protons 36 electrons 30 neutron because of 29 isotope

Answer:

D.organism

Explanation:

A fungus from the kingdom fungi is an organism

Answer:

D. organism

......................

Answer:

Explanation:

p-diaminobenzene is popularly known as p-phenylenediamine. It undergoes a condensation reaction with metal halides. As a white solid (p-diaminobenzene), it can be darkened by air oxidation. The reaction showing the condensation of p-phenylenediamine with (CoCl)₂ can be seen in the image attached below.

Explanation:

hope it helps you

Answer:

6200 meters

Explanation:

To convert from km to m you have to multiply the number by a thousand

Answer:

6.2×10^3 m

Explanation:

6.20×1000=6200m

In scientific notation 6200 = 6.2×10^3

Answer:

each planet has a different force of gravity

Explanation:

Weight = mass× gravity

As gravity changes from place to place and also from planet to planet so weight changes.

Answer:

hope this help

Explanation:

change: volume of solid , volume of liquid , the volume of gases

not change: the shape of solid , the shape of liquid , the shape of gases

Answer: answer is C on Edge

Explanation:

An arrow is fired at a target on a high wal. The energy change between the moment the arrow is fired and the moment it hits the target is the kinetic energy decreases as potential energy increases. The correct option is c.

Energy neither be created nor destroyed. It just only is transferred from one form to another form. This is called energy change. When any reactions happen, one form of energy is changed into another form.

There are many kinds of energy. These energies are kinetic energy, potential energy, gravitational energy, etc. Kinetic energy is the energy that is used when any work is done. Potential energy is the energy that is stored form of energy.

Therefore, the correct option is c, The kinetic energy decreases as potential energy increases.

To learn more about energy change, refer to the link:

https://brainly.com/question/22255429

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