Which of the following is an element?
A.
magnesium chloride salt (MgCl)
B.
hydrochloric acid (HCl)
C.
carbon monoxide gas (CO)
D.
zinc metal (Zn)

Answer:

The answer would be Helium-8.

Answer:

[tex]\boxed {\boxed {\sf \rho \approx 7.917 \ g/mL}}[/tex]

Explanation

Density can be found by dividing the mass by the volume.

[tex]\rho=\frac{m}{v}[/tex]

We know the iron sheet has a mass of 28.5 grams and the volume is 3.60 milliliters.

[tex]m= 28.5 \ g \\d= 3.60 \ mL[/tex]

Substitute the values into the formula.

[tex]\rho=\frac{28.5 \ g}{ 3.60 \ mL}[/tex]

Divide.

[tex]\rho = 7.91666667 \ g/mL[/tex]

Let's round to the nearest thousandth.

The 6 in the ten-thousandth tells us to round the 6 to a 7.

[tex]\rho \approx 7.917 \ g/mL[/tex]

The density of iron is about 7.917 grams per milliliter.

Answer:

It appears to be

Explanation:

I did that question.

Answer: Water

Explanation:

Answer:

272.31× 10²³ atom of strontium

Explanation:

Given data:

Number of moles of strontium = 45.22 mol

Number of atoms = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.  The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ atoms

45.22 mol × 6.022 × 10²³ atom / 1 mol

272.31× 10²³ atom

Answer : The correct option is, [tex]Zn^{2+}[/tex]

Explanation :

Or we can say that, oxidation reaction occurs when a reactant losses electrons in the reaction.

Or we can say that, reduction reaction occurs when a reactant gains electrons in the reaction.

According to the electrochemical series, [tex]Zn^{2+}[/tex] most likely to be reduced because

Hence, the ion most likely to be reduced is [tex]Zn^{2+}[/tex].

The most likely to be reduced is Cu ²⁺. Because it is stronger oxidizing agent.

In a redox chemical reaction, an oxidizing agent is a material that "accepts" or "receives" an electron from a reducing agent. So every substance that oxidizes another material is an oxidant.

A material that induces oxidation by receiving electrons becomes reduced when it acts as an oxidizing agent. A chemical that reduces something by gaining electrons is said to be an oxidizing agent.

The reduction that takes place, which involves Cu, is the one with the highest positive reduction potential. This is because either Cu2+ is a stronger oxidizing agent than Zn2+ or Cu2+ is more likely to be reduced than Zn2+.

Thus, option D is correct.

To learn more about oxidizing agent, follow the link;

https://brainly.com/question/10547418

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Answer:

B

Explanation:

Answer: Fe3+

Explanation: j took the quiz

a. 381.27 m/s

b. the rate of effusion of sulfur dioxide = 2.5 faster than nitrogen triiodide

Given

T = 100 + 273 = 373 K

Required

a. the gas speedi

b. The rate of effusion comparison

Solution

a.

Average velocities of gases can be expressed as root-mean-square averages. (V rms)  

[tex]\large {\boxed {\bold {v_ {rms} = \sqrt {\dfrac {3RT} {Mm}}}}[/tex]

R = gas constant, T = temperature, Mm = molar mass of the gas particles  

From the question  

R = 8,314 J / mol K  

T = temperature  

Mm = molar mass, kg / mol  

Molar mass of Sulfur dioxide = 64 g/mol = 0.064 kg/mol

[tex]\tt v=\sqrt{\dfrac{3\times 8.314\times 373}{0.064} }\\\\v=381.27~m/s[/tex]

b. the effusion rates of two gases = the square root of the inverse of their molar masses:  

[tex]\rm \dfrac{r_1}{r_2}=\sqrt{\dfrac{M_2}{M_1} }[/tex]

M₁ = molar mass sulfur dioxide = 64

M₂ =  molar mass nitrogen triodide = 395

[tex]\tt \dfrac{r_1}{r_2}=\sqrt{\dfrac{395}{64} }=\dfrac{20}{8}=2.5[/tex]

the rate of effusion of sulfur dioxide = 2.5 faster than nitrogen triodide

Answer:

this is a multiple choice question where are the answers

Explanation:

Answer:

2k

Explanation:

Answer:

+2k

Explanation:

Because +++k and -k answer is ++k

One +Cancel with -

Answer:

1 Once proteins, fats and carbohydrates are digested, absorption takes place in the small intestine.

2 if we eat food we get energy, but if there weren't chemical reaction in your body nothing happens.

Explanation:

1 Most of the digestion occurs in the first part of the small intestine while the absorption of broken down nutrients, water, vitamins, and minerals occurs in the rest of it.

The molarity of ethanol in the solution is 0.217 M

Given

1% by mass

density = 0.996 g/ml

Required

The molarity

Solution

mass/ml of Ethanol :

1% x 0.996 g/ml = 0.00996 g/ml

For 1 L solution :

0.00996 g/ml x 1000 ml/L = 9.96 g/L

Convert to mol/L(MW ethanol=46 g/mol) :

9.96 g/L : 46 g/mol= 0.217 mol/L = 0.217 M

Or you can use equation :

[tex]\tt M=\dfrac{\%mass\times \rho\times 10}{MW}\\\\M=\dfrac{1\times 0.996\times 10}{46}=0.217[/tex]

Answer:

Please see the attached image. The one on the left is the first one and the one on the right is the second one.

Hope that helps.

Answer: electrons

Explanation:

During oxidation and reduction, both of which are redox reactions, electrons are transferred.

Answer:

false

Explanation:

Carbon atoms are found in hydrocarbons, naturally occurring compound with carbon and hydrogen, but there are molecules in nature that contain beside carbon and hydrogen, oxygen and nitrogen too. In this compounds there are carbon-oxygen and carbon-nitrogen covalent bonds.

Bellow you may see the chemical structure of adrenaline, a hormon found in the human body, were the oxygen (red) and nitrogen (blue) are bonded to carbon.

Answer:

false

Explanation:

Carbon atoms often naturally bond with each other in chains, rings, plates, or networks, and they also bond readily with hydrogen, oxygen, nitrogen, sulfur, phosphorus, and the halogens.

Answer:

Speed

Explanation:

On a distance - time graph, the slope of the line indicates the speed of the object.

Speed is the rate of change of distance with time.

  Speed  = [tex]\frac{distance}{time}[/tex]  

Now, the slope is the change in distance with the change time which is commensurate with the speed equation.

For a displacement - time graph, the slope is the velocity.

 Therefore the slope of a distance - time graph is its speed.

Answer: The prediction that human population is likely to increase may result in severe problems like global warming, extinction of animals due to human activities, et cetera.

Explanation:

The human population needs resources to survive, they use the resources in such a way that it is being exploited, the trees will be cut in such a large numbers that it will affect the animals depending them.

The human population also uses fossil fuels, burning of which releases harmful gases in the environment.

The usage of technology also comes with the curse of global warming because of release of green house gases such as chlorofluorocarbon.

With an increase in human population, there can be seen many harmful effects on environment.

Answer:

whatttttttttyu[poiuytrtyuiopoiuygtfdfghjkjhgfdfghjk

Explanation:

Answer:

They all have 7 valence electrons on it's outer shell.

Answer:

I have that question rn, I think the best answer is that they tend to form ions with a -1 electric charge.

Explanation:

Answer:

Well why didn't you do it? Have a great day and I am so sorry for wasting your points I don't need them. I hope someone helps!! ;)

Explanation:

two

Explanation:

When two or more objects come in contact with each other this is called contact force

Answer:

B. Impulse

Explanation:

A= she is not resisting buying the car

B= She bought the car right away(impulse)

C = She did not plan ahead on what car she would buy

D= Not reasonable

Answer:

Oh it is convention

Explanation:

because the heat transfer is through fluids

Answer:

[tex]C_4H_5[/tex]

Explanation:

Hello!

In this case, since the combustion analysis provides us the yielded mass of both water and carbon dioxide, as the sources of hydrogen and carbon in the hydrocarbon, we are able to compute the moles of each via the following mole-mass relationships:

[tex]n_H=1.36gH_2O*\frac{1molH_2O}{18.02gH_2O}*\frac{2molH}{1molH_2O}=0.151molH\\\\n_C=5.22gCO_2*\frac{1molCO_2}{44.01gCO_2}*\frac{1molC}{1molCO_2}=0.119molC[/tex]

Now, we divide those moles by the fewest ones (those of carbon) in order to compute their subscripts in the empirical formula:

[tex]C: \frac{0.119}{0.119} = 1 \\\\H:\frac{0.151}{0.119} = 1.27[/tex]

However we need whole numbers, that is why we multiply each subscript by 4 to get 4 for carbon and 5.08 ≅ 5 for hydrogen:

[tex]C_4H_5[/tex]

Best regards!

Answer:

The heat absorbed by the water is 228,948.48 J

Explanation:

Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

In this way, between heat and temperature there is a direct proportional relationship (Two magnitudes are directly proportional when there is a constant so that when one of the magnitudes increases, the other also decreases; and the same happens when either of the two decreases .). The constant of proportionality depends on the substance that constitutes the body and its mass, and is the product of the specific heat and the mass of the body. So, the equation that allows to calculate heat exchanges is:

Q = c * m * ΔT

where Q is the heat exchanged by a body of mass m, constituted by a substance of specific heat c and where ΔT is the variation in temperature.

In this case:

Replacing:

Q= 4.184 [tex]\frac{J}{g*C}[/tex] *855 g* 64 C

Solving:

Q= 228,948.48 J

The heat absorbed by the water is 228,948.48 J

Moles in the container : 0.306

Given

30 g of H3PO4

Required

moles in container

Solution

A mole is a unit of many particles (atoms, molecules, ions) where 1 mole is the number of particles contained in a substance that is the same amount as many atoms in 12 gr C-12  

1 mole = 6.02.10²³ particles  

While the number of moles can also be obtained by dividing the mass (in grams) with the molar mass of element or molecule  

MW of H3PO4 = 3.1 + 31 + 4.16 = 98 g/mol

mol = mass : MW

mol = 30 : 98

mol = 0.306

Moles of Carbon dioxide(CO2) = 2

Given

Reaction

2 C2H6 (g) + 7 O2 (g) —+ 4CO2 (g) + 6 H20 (g)

Required

moles of carbon dioxide

Solution

The reaction coefficient shows the mole ratio of the compounds in the reaction equation (reactants and products)

From the equation, mol ratio of C2H6 : CO2 = 2 : 4, so mol CO2 :

mol CO2 = (4/2) x mol  C2H6

mol CO2 = 2 x 1

mol CO2 = 2