.. Identify how many atoms of each element are in the molecule: H2O2​

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:

[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:

[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:

[tex]c=0.127\ J/g^{\circ} C[/tex]

Explanation:

Given that,

Mass of the sample, m = 275 g

It required 10.75 kJ of heat to change its temperature from 21.2 °C to its melting temperature, 327.5 °C.

We need to find the specific heat of the metal. The heat required by a metal sample is given by :

[tex]Q=mc\Delta T[/tex]

c is specific heat of the metal

[tex]c=\dfrac{Q}{m\Delta T}\\\\c=\dfrac{10.75\times 10^3\ J}{275\times (327.5 -21.2)}\\\\=0.127\ J/g^{\circ} C[/tex]

So, the specific heat of metal is [tex]0.127\ J/g^{\circ} C[/tex].

Answer:

None have backbones

No cell walls

Multicellular

Includes radial or bilateral body symmetry.

Explanation:

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:

Non polar covlant

Explanation:

Answer:

The relationship is the "variation of vapour pressure with temperature" or " the effect of vapour pressure on the melting and boiling points in a phase"

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:

Vav=d/t

Explanation:

Because the question already gave d=90m and t=20s. Because the car is the thing that can not travel the same distances at the same times.So the equation is V[tex]\\_{av}[/tex]=[tex]\frac{d}{t} \\[/tex]

Answer:

They are all mixture

Explanation:

last option

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:

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: The mole fraction of chloroform in this solution is 0.41

Explanation:

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]

a) moles of [tex]CHCl_3[/tex]

[tex]\text{Number of moles}=\frac{49g}{119g/mol}=0.41moles[/tex]

b) moles of [tex]CH_3COBr[/tex]

[tex]\text{Number of moles}=\frac{73g}{123g/mol}=0.59moles[/tex]

To calculate the mole fraction, we use the formula:

[tex]\text{Mole fraction of a component}=\frac{\text{Moles of the component}}{\text{total moles}}[/tex]

[tex]\text{Mole fraction of chloroform}=\frac{\text{Moles of chloroform}}{\text{total moles}}=\frac{0.41}{0.41+0.59}=0.41[/tex]

The mole fraction of chloroform in this solution is 0.41

Answer:

D. Oxidation

Explanation:

In an electrolytic cell, oxidation (the loss of electrons) takes place at the anode. At the cathode reduction takes place.

A mnemonic technique that could be used is that the process that starts with a vowel (Oxidation) takes place at the place that also starts with a vowel (Anode).

Identify the type of solid from the description. Select from the following choices: metallic solid, network solid, molecular solid, ionic solid, or amorphous solid. a. This solid is ductile and conducts electricity.b. This solid is not conductive and has a low melting point.

Answer:

See explanation

Explanation:

A is a Metallic Solid

Let us look again at the physical properties of metals;

Metals are

We can now see that both ductility and electrical conductivity are metallic properties.

B is a Molecular solid

Molecules are formed when atoms share electrons. In molecules, there are no free electrons hence molecules do not conduct electricity.

Secondly, molecules are held together in the solid state by weak dispersion forces hence molecular solids have a low melting point.

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:

Two vectors are equal if they have the same magnitude and the same direction. Just like scalars which can have positive or negative values, vectors can also be positive or negative. A negative vector is a vector which points in the direction opposite to the reference positive direction.

The answer is A. The vibration caused by the waves through the air eventually weaken, which is why sound diminishes easily over distance.

Answer:

Theory- 1 to 7

Explanation:

Exercise- 8 to 25

ect

The right alternative is Option D (0.78 V).

According to the question,

By putting the values, we get

Cu+2 + 2e → Cu E = 0.52 V

Ag+1 + 1e Ag E° = 0.78 V

= 1.23 - 0.45

= 0.78.

negative

The standard cell potential is quite negative, so the reaction will not occur spontaneously as written.

Missing parts of the question.

Using the two cell reduction potentials shown for their corresponding reaction, calculate the cell potential for a voltaic cell made from these two systems: 0.78.

Cu+2 + 2e → Cu E = 0.52 V

Ag+1 + 1e Ag E° = 0.80 V

options:

A)

0.28 V

B)

–1.32 V

C)

1.32 V

D)

–0.28 V

Learn more about cell potential at

https://brainly.com/question/1313684

#SPJ2

Answer:

[tex]6K _{(s)} + N _{2(g)} = = > \:2K _{3} N _{(s)} [/tex]

Potassium nitride

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:

The solubility of lead chromate : s= 5.29 x 10⁻⁷ mol/L

Given

Ksp  for PbCl,=2.8x10*-13 mole/dmº

PbCrO4

Required

The solubility

Solution

P b C r O ₄ ( s ) ⇌ P b²⁺( a q) +C r O ₄ ⁻²( a q )

s                     s               s

s= solubility

Ksp P b C r O ₄  = s²

K s p  = [ P b ²⁺] [C r O ₄ ⁻² ]= 2.8x10⁻¹³

s = √2.8x10⁻¹³

s= 5.29 x 10⁻⁷ mol/L

Answer: Alloy

Explanation: gold is an alloy, or mixture of metals

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:

[tex]c=0.2\ J/g^{\circ} C[/tex]

Explanation:

Given that,

Mass of a glass, m = 4 g

Initial temperature, [tex]T_i=5^{\circ} C[/tex]

Final temperature, [tex]T_f=45^{\circ} C[/tex]

Heat absorbed, Q = 32 J

We need to find the specific heat of the glass. The formula for the heat absorbed is given by :

[tex]Q=mc\Delta T\\\\c=\dfrac{Q}{m\Delta T}\\\\c=\dfrac{32\ J}{4\ g\times (45-5)^{\circ} C}\\\\=0.2\ J/g^{\circ} C[/tex]

So, the required specific heat of the glass is [tex]0.2\ J/g^{\circ} C[/tex].