240 g of water (specific heat = 4.186 J/g°C, initial temperature = 20°C) is mixed with an
unknown mass of iron (specific heat = 0.444 J/gºC, initial temperature 500°C). When
equilibrium is reached, the system has a temperature of 42°С. Find the mass of iron.

Answer:

Sis I think it happened with me but I am not able to remember if u want u can share if it happened with u

Answer:

True

Explanation:

Answer:

Explanation:

Answer:

The molecules in gasoline (octane, the chemical formula shown) contain chemical energy. This energy is transformed into kinetic energy that allows a car to race on a racetrack.

Solution :

Given :

Hydrogen iodide decomposes to hydrogen and iodine gas

    [tex]$2 HI \ \ \ \Leftrightarrow \ \ \ \ H_2 \ \ \\ + \ \ I_2 $[/tex]

I    0.148            0          0

C     -2a           +a          +a

E  0.148-2a      a            a

We know

[tex]$k_p=\frac{P(H_2)P(I_2)}{P(HI)^2}$[/tex]

[tex]$0.016=\frac{a^2}{(0.148-2a)^2}$[/tex]

[tex]$0.016^{1/2}=\frac{a}{0.148-2a}$[/tex]

[tex]$0.12649=\frac{a}{0.148-2a}$[/tex]

0.0187 = 1.2529 a

a = 0.0149

Therefore

P(HI) = 0.148 - 2a

        = 0.148 - 2(0.0149)

        = 0.1182 atm

P([tex]$H_2$[/tex]) =  a

        = 0.0149 atm

P([tex]$I_2$[/tex]) =  a

        = 0.0149 atm

Answer:

B, No reaction will occur

Explanation:

Copper as compared to lead is less reactive. This is the reason when  lead is added to copper nitrate solution, it replaces the copper and itself combines with nitrate to form lead nitrate aqueous solution

Lead + Copper(II) nitrate → Copper + Lead (II) nitrate

The same is not the case when the reaction is revered i.e Cu is added to Pb NO3 solution.

Hence, option B is correct

Answer:

See Explanation

Explanation:

In thermodynamics theory the Free Energy (ΔG) of a chemical system is described by the expression ΔG = ΔG° + RTlnQ. When chemical system is at equilibrium ΔG = 0. Substituting into the system expression gives ...

0 = ΔG° + RTlnKc, which rearranges to ΔG° = - RTlnKc.  ΔG° in electrochemical terms gives ΔG° = - nFE°, where n = charge transfer, F = Faraday Constant = 96,500 amp·sec and E° = Standard Reduction Potential of the electrochemical system of interest.

Substituting into the ΔG° expression above gives

-nFE°(cell) = -RTlnKc => E°(cell) = (-RT/-nF)lnKc = (2.303·R·T/n·F)logKc

=> E°(cell) = (0.0592/n)logKc = E°(Reduction) - E°(Oxidation)

Application example:

Calculate the Kc value for a Zinc/Copper electrochemical cell.

Zn° => Zn⁺² + 2e⁻  ;    E°(Zn) = -0.76 volt  

Cu° => Cu⁺² + 2e⁻ ;    E°(Cu) =  0.34 volt

By natural process, charge transfer occurs from the more negative reduction potential to the more positive reduction potential.

That is,

           Zn° => Zn⁺² + 2e⁻ (Oxidation Rxn)

Cu⁺² + 2e⁻ => Cu°             (Reduction Rxn)

E°(Zn/Cu) = (0.0592/n)logKc

= (0.0592/2)logKc = E°(Cu) - E°(Zn) = 0.34v - (-0.76v) = 1.10v

=> logKc = 2(1.10)/0.0592 = 37.2

=> Kc = 10³⁷°² = 1.45 x 10³⁷

Answer: 41.0

Explanation: When you multiply the two numbers you get 41 but you need to have the same amount of significant numbers as the number in the problem with the least significant numbers. I hope this helps

Answer:

600

Explanation:

there's 1 mole in every nitroglycerin

I think

Answer:

I think B

Explanation:

There are more negative ions than positive ions

Answer:

milliliters

Explanation:

Is going to be milliliters because in the metric system of measurement,the most common unit of volume are milliliters and liters

Answer:

the original substances in any chemical reaction. products. the resulting substances in any....chromium(III) oxide, and water. (NH4)2Cr2O7(s) → N2(g) + Cr2O3(s) + 4H2O(g).

Explanation: they could be grouped by how they reproduce or they can be grouped by if there hetero or autotrophic

Answer:

chlorine ~ 30%

zinc ~ 28%

oxygen ~ 41%

Explanation:

[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]

45° Celsius

Formula (113°F − 32) × 5/9 = 45°C

The equation in the symbolic form can be written as,

[tex]\tau \;- > e- + {\bar{\nu }} e + \nu\tau[/tex]

The total number of quarks in a helium nucleus consisting of 2 protons and 2 neutrons is 12 quarks.

Any of a family of particles (such as electrons, muons, and neutrinos) that have spin quantum number ¹/₂ and that experience no strong forces.

The equation in the symbolic form can be written as,

[tex]\tau \;- > e- + {\bar{\nu }} e + \nu\tau[/tex]

Charge on the left side = -1

Charge on the right side = -1+0+0 = -1

As the charge on the electron antineutrino,  [tex]{\bar{\nu }}[/tex] e and the tau neutrino,  [tex]\nu\tau[/tex] are zero each.

Thus, charge on left side = charge on right side

Or, the equation is in accordance with charge conservation.

Lapton number of left side = 1

Laptop number of right side = 1-1+1 = 1

This is because, lapton number of the particles involved are,

Tau lapton, [tex]\tau[/tex]-1 = 1,

Electron, e-1 = 1,

Electron antineutrino,  [tex]{\bar{\nu }}[/tex]e = -1,

Tau neutrino, [tex]\nu\tau[/tex]= 1,

Thus, lapton number of left side = lapton number of right side

So, the equation obeys lapton number conservation.

2.

The total number quarks in a helium nucleus which is composed of 2 protons (positively charged particle) and 2 neutrons (uncharged particle) is:

Since there 3 quarks in each nucleon, 4 nucleons would have a total of 12 quarks.

Just simply multiply 3 quarks by the number of nucleons:

So, 3 (quarks) x 4 (nucleons) = 12 quarks

Therefore, there are 12 quarks in 4 nucleons.

Learn more about lepton decays here:

https://brainly.com/question/12044097

#SPJ1

Answer:

5.01 x 10^-6 M

Explanation:

PH= -log [H+]

[H+] = 10^-PH

Answer:

What is the question your asking?

Explanation:

All atoms of the same element have the same properties.

Answer:

The correct answer is - neutrons.

Explanation:

Uranium has various isotopes found naturally that are three 238U, 235U, and 234U. Uranium has an atomic number of 92 which means there are 92 protons and 92 electrons in the atomic structure.

Isotopes have the same number of protons but a different number of neutrons that can vary from 141 to 146. U-238 has 146 neutrons in the nucleus, whereas 235 U has 143 neutrons.

The U- 238 has more neutrons than U- 235. Atomic mass is the sum total of the nucleons or protons and neutrons.

What are Isotopes?

They are the different variants of the same molecules which have the same number of protons but the different number of neutrons.

Atomic mass is the sum total of the nucleons or protons and neutrons. The atomic number of Uranium is 92, the rest of the mass comes from neutrons.

Therefore, the U- 238 has more neutrons than U- 235.

Learn more about Isotopes:

https://brainly.com/question/9099776

Answer:

I would put the final answer choice: "Scientists must first develop certain technologies before missions can be completed"

Explanation:

The first option is partially true, but we have ways around it.

The second option is straight-up false.

The third option doesn't make much sense, how can one work with technology that will be developed in the future and doesn't yet exist?

Therefore, the fourth option is the best.

Hope this helps

-cyber

Answer:

high use of mineral resources

Explanation:

brainliest pls

Answer:

Eukaryotic cells have a true nucleus, which means the cell's DNA is surrounded by a membrane. Therefore, the nucleus houses the cell's DNA and directs the synthesis of proteins and ribosomes, the cellular organelles responsible for protein synthesis.

Ribosomes are the sites in a cell in which protein synthesis takes place. ... Within the ribosome, the rRNA molecules direct the catalytic steps of protein synthesis — the stitching together of amino acids to make a protein molecule.

Answer:

0.0428 kg or 42.8 g

Explanation:

Applying,

Q = cmΔt.............. Equation 1

Where Q = heat lost of heat gained, c = specific heat capacity of copper, m = mass of copper, Δt = temperature change.

make m the subject of the equation above

m = Q/cΔt.................. Equation 2

From the question,

Given: Q = 428 J, Δt = 25 °C

Constant: c = 400 J/kg.°C

Substitute these values into equation 2

m = 428/(25×400)

m = 0.0428 kg

m = 42.8 g

Answer:

evaporation is the process

Answer:

Explanation:

Evaporation is the process of becoming a vapor. The process of extracting moisture as by heat.

Evaporation is the process of change from a liquid to a gas at temperatures below the boiling point.

Therefore, the final answer is evaporation.

Answer:

1. 1.33 gram of carbon

2. 2.38g of carbon dioxide

Explanation:

From the given information:

Total amount of CO₂ = 4.86 grams

Atomic mass of C = 12 g/mole

molar mass of CO₂ = 44 g/mole

∴

The mass of the Carbon (C) in grams is:

[tex]= Total\ amount \ of \ CO_2 \times \dfrac{12 \ g/mol}{44 \ g/mol}[/tex]

[tex]= 4.86 \ g \times \dfrac{12 \ g/mol}{44 \ g/mol}[/tex]

= 1.33 gram of carbon

2.

Here, the total amount of CO₂ = unknown

Atomic mass of O₂ = 32 g/mole

molar mass of CO₂ = 44 g/mole

amount of oxygen = 1.73 g

∴

The mass of CO₂ = [tex]Total \ amount \ of \ O_2 \times \dfrac{44 \ g/mol}{32\ g/mol}[/tex]

[tex]=1.73 \times \dfrac{44 \ g/mol}{32\ g/mol}[/tex]

= 2.38 g of carbon dioxide

Answer:

it contains 0.599 g i hope it helps