when dilute HCL is added to zinc pieces taken in a test tube​

Answer:

3Fe²⁺ + Cl₂ ⇒ 2Fe³⁺ + 2Cl⁻

Explanation:

manipulate the problem to match charges and have the same amount of reactants and products on both sides.

Answer:

When forming ions, elements typically gain or lose the minimum number of electrons necessary to achieve a full octet. For example, fluorine has seven valence electrons, so it is most likely to gain one electron to form an ion with a 1- charge

Explanation:

Answer:

7

Explanation:

a-P-e-X

Answer:

The Best Answer would be B but the correct answer is A+B --> AB

Explanation:

His distance and displacement are the same, which was 400 m

Given

Distance = 400 m

time = 2 min

Required

Distance and displacement

Solution

Distance is a scalar quantity that indicates the length of the trajectory that is traveled by an object within a certain interval. Distance has no direction, only has magnitude  

Can be simplified distance = totals traveled  

Displacement is a vector quantity that shows changes in the position of objects in a certain interval of time. Displacement has magnitude and direction  

Can be simplified displacement = distanced traveled from starting point to ending point  

From the definition above shows that the displacement and the distance that he traveled have the same value (magnitude), which is equal to 400 m

The value of the two will be different if he starts and finishes at the same point, then the displacement value is zero while the distance he has traveled is still 0

Answer:

Phosphorus.

Explanation:

Phosphorus is the important fertilizer which comes through the dust storms of Sahara desert and provides this nutrient to the soils of the Amazon basin. Phosphorus is an important macronutrient that is necessary for the growth and development of plants so we can conclude that this dust storms are very important for the fertility of the soils present in Amazon basin.

Answer:

The theoretical yield of carbonic acid is 1.24 grams.

Explanation:

The balanced equation for the formation of carbonic acid by the reaction of carbon dioxide with water is:

CO₂ + H₂O → H₂CO₃

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of reactant and product participate:

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:

P * V = n * R * T

Moles of carbon dioxide can be calculated using ideal gas law equation. In this case:

Replacing:

1 atm* 0.495 L= n* 0.082 [tex]\frac{atm*L}{mol*K}[/tex] *298 K

Solving:

[tex]n=\frac{1 atm*0.495 L}{0.082\frac{atm*L}{mol*K}*298 K }[/tex]

n= 0.02 moles

Then, by reaction stoichiometry 0.02 moles of carbon dioxide produces 0.02 moles of carbonic acid.

Since the molar mass of carbonic acid is 62.03 g/mol, then you can apply the following rule of three: if there are 62.03 grams in 1 mole, how much mass is there in 0.02 moles?

[tex]mass=\frac{0.02 moles*62.03 grams}{1 mole}[/tex]

mass= 1.24 grams

The theoretical yield of carbonic acid is 1.24 grams.

Answer:

Frequency = 6.16 ×10¹⁴ Hz

λ = 4.87×10² nm

Explanation:

In case of hydrogen atom energy associated with nth state is,

En =  -13.6/n²

For n = 2

E₂ = -13.6 / 2²

E₂ = -13.6/4

E₂ = -3.4 ev

Kinetic energy of electron = -E₂ = 3.4 ev

For n = 4

E₄ = -13.6 / 4²

E₄ = -13.6/16

E₄ = -0.85 ev

Kinetic energy of electron = -E₄ = 0.85 ev

Wavelength of radiation emitted:

E = hc/λ = E₄ - E₂

hc/λ = E₄ - E₂

by putting values,

6.63×10⁻³⁴Js × 3×10⁸m/s / λ = -0.85ev   - (-3.4ev )

6.63×10⁻³⁴ Js× 3×10⁸m/s / λ = 2.55 ev

λ = 6.63×10⁻³⁴ Js× 3×10⁸m/s  /2.55ev

λ = 6.63×10⁻³⁴ Js× 3×10⁸m/s  /2.55× 1.6×10⁻¹⁹ J

λ = 19.89 ×10⁻²⁶ Jm / 2.55× 1.6×10⁻¹⁹ J

λ = 19.89 ×10⁻²⁶ Jm / 4.08×10⁻¹⁹ J

λ = 4.87×10⁻⁷ m

m to nm:

4.87×10⁻⁷ m ×10⁹nm/1 m

4.87×10² nm

Frequency:

Frequency = speed of electron / wavelength

by putting values,

Frequency = 3×10⁸m/s /4.87×10⁻⁷ m

Frequency = 6.16 ×10¹⁴ s⁻¹

s⁻¹ = Hz

Frequency = 6.16 ×10¹⁴ Hz

Answer:

c I am pretty sure it's c because I learned this today in science and I think that what it is but if it's not see then it's I don't know

Answer: Gravity is considered a universal force because it acts between any two masses anywhere in the universe.

Answer:

Gravity (from Latin gravitas 'weight'[1]), or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light[2]—are brought toward (or gravitate toward) one another. On Earth, gravity gives weight to physical objects, and the Moon's gravity causes the ocean tides.

Explanation:

Difference between 63 and 65 = 2.

(63.55 - 63) / 2 * 100% = 27.5%.

(65 - 63.55) / 2 * 100% = 72.5%.

Hence there is 72.5% of the isotope with atomic mass 63 and 27.5% of the isotope with atomic mass 65 in copper.

Answer:

3 M

Explanation:

Molarity is calculated by dividing the moles of the solute by the liters of solution. In this problem, we are given that the mass of the solution is 353.4 g and that the mass of the solute (H2SO4) is 25% of this.

Thus, you get that the mass of the solute is 88.35 g.

Next, you must convert the mass of the solute into moles. You must use the periodic table to find the molar mass of the solute in order to do the conversion.

Thus, you get that the number of moles of solute is 0.90.

Molarity is then = 0.90 mol/.300 L = 3 M.

The molarity of a 300ml solution of mass 353.4 g which is 25%by mass H₂SO₄ is 2.94 molar.It is calculated from the number of moles of sulphuric acid.

Molarity is a term used to represent the concentration of a solution. Mathematically it is the ratio of the number of moles of solute to the volume of solution in liter.

The mass percent of substance is the ratio of mass of that substance to the total mass. Here, the total mass of the solution is 353.4 g and the solute acid is 25% by mass. Thus mass of the solute is :

353.4 × 25 /100 = 88.3 g.

The molar mass of sulphuric acid is 100 g/mol. Thus number of moles of solute is 88.3 g/100 g/mol = 0.88 moles.

The volume of the solution is 300 ml or 0.3 liter. Now, the molarity of the solution can be calculated as follows:

Molarity = no.of moles of solute/volume in L

              = 0.88 mol / 0.3 L

              = 2.94 mol/L.

Hence, the molarity of the solution is 2.94 molar.

To find more about molarity, refer the link below:

https://brainly.com/question/4401006

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Answer is:

When one person exerts more force than the other so that the forces are unbalanced........ maybe, im not sure if im right

Answer:

c

Explanation:

Answer:

Total pressure =  56.77 bar

Explanation:

Given data:

Mass of dioxygen = 8 g

Mass of dihydrogen = 4 g

Volume of vessel = 1 dm³

Temperature = 27°C (27+273 = 300 K)

R = 0.083 bar.dm³ / mol.K

Total pressure = ?

Solution:

Number of moles of dioxygen:

Number of moles = mass/molar mass

Number of moles = 8 g/ 32 g/mol

Number of moles = 0.25 mol

Pressure of dioxygen:

PV = nRT

P = nRT/V

P = 0.25 mol × 0.083 bar.dm³ / mol.K × 300 K / 1 dm³

P = 6.97 bar.dm³  /1 dm³

P = 6.97 bar

Number of moles of dihydrogen:

Number of moles = mass/molar mass

Number of moles = 4 g/ 2 g/mol

Number of moles = 2 mol

Pressure of dihydrogen:

PV = nRT

P = nRT/V

P = 2 mol × 0.083 bar.dm³ / mol.K × 300 K / 1 dm³

P = 49.8 bar.dm³  /1 dm³

P = 49.8 bar

Total pressure of mixture in a vessel:

Total pressure = P (O₂) + P(H₂)

Total pressure =  6.97 bar + 49.8 bar

Total pressure =  56.77 bar

Answer:

Clay and Pumice can both be said to be Porous but they are not Permeable

Explanation:

A porous substance is one which have pores in in through which air or liquid can pass through. Both clay and pumice are porous due to the presence of pores in them. These pores allow air to pass through them. However, since the pores are not well connected water do no pass through them. As a result, clay vessels can hold water within them and pumice floats on water.

Permeability is the ability of a substance to allow other substances to pass through. Both clay and pumice have low permeability, as a result they do not allow water to pass through them. Rather, water runs over their surface when poured over them.

Answer:

Clay and Pumice can both be said to be Porous but they are not Permeable

Explanation:

Answer:

Kinetic energy.

Explanation:

Answer:

true

Explanation:

its A

The above statement is considered to be correct and true.

The Occupational Safety and Health Administration (OSHA) is a federal agency that is saddled with the responsibility of assuring and ensuring a safe and healthy working conditions for an employee or group of employees by doing the following;

According to the Occupational Safety and Health Administration (OSHA), trainings on the adoption and application of safety precautions (tools) such as wearing a personal protective equipment (PPE); face masks (respirators), ear plugs, safety boots, gloves, helmet, etc., are very important and are essentially to be used by all employees (workers) while working in hazard prone environments or industries.  

However, when an employee fails to strictly adhere to the recommended OSHA safety precautions, he or she is more likely to sustain a work-related accident or injury from a fall. Thus, this would negatively affect (impact) the employee because it results in him or her being absent from work (time off) and requires some costs to pay for medicals (medical cost).

In conclusion, injuries from work related falls can affect employees by resulting in time off and medical cost.

Find more information: https://brainly.com/question/15442363

Answer:

chloroplasts, cell walls, or intracellular vacuoles

Explanation:

You didn't list the following, but I'm guessing it is chloroplasts, cell walls, or intracellular vacuoles

Answer:

Explanation:

An equation showing only what is involved in the reaction.

a o e x

Answer:

I dont know how to take a picture so I will just tell you the answer. The answer   is no.

Explanation:

Hope this helps.    :)      :D

The heat required : 840 J

Given

mass of water = 20 g

Temperature : 30°C to 40°C

Required

Heat to raise the temperature

Solution

Heat can be calculated using the formula:  

Q = mc∆T  

Q = heat, J  

m = mass, g  

c = specific heat, joules / g ° C  (for water= 4.18 J/g° C)

∆T = temperature difference, ° C / K  

The heat :

[tex]\tt Q=20\times 4.2\times (40-30)\\\\Q=\boxed{\bold{840~J}}[/tex]

Answer:

A

Explanation:

A

Answer:

0.855 moles are present in 34.2 g of Ca

The percent by  mass of H₂O in the hydrated compound, Na₂CO₃.xH₂O = 64.13%

Given

90 g sample Na₂CO₃.xH₂O

32.28 g Na₂CO₃

Required

The percent by  mass of H₂O

Solution

mass of H₂O = mass of sample - mass of the anhydrous salt, Na₂CO₃

[tex]\tt mass~H_2O=90-32.28=57.72~g[/tex]

The percent by mass :

[tex]\tt \%mass~H_2O=\dfrac{mass~H_2O}{mass~sample}\times 100\%\\\\\%mass~H_2O=\dfrac{57.72}{90}\times 100\%\\\\\%mass~H_2O=64.13\%[/tex]

Answer:

C) first

Explanation:

E cell = 1.962 V

Given

E° cell = 2.00 V

Required

E cell at 298 K

Solution

The potential cell for nonstandard conditions we can use the Nernst equation  

[tex]\rm E = E ^ o -\dfrac {RT} {nF} lnQ[/tex]

For temperature T = 298 K,  

[tex]\rm E = E ^ o -\dfrac {0.0592V} {n} log \: Q[/tex]

Reaction

3A(s) + B+3(aq) → 3A+(aq) + B(s)

Half Reaction

3A(s)⇒3A⁺(aq)+3e⁻

B⁺³(aq)+3e⁻⇒B(s)

n = 3 (3 electron transfer)

Q = the reaction quotient  :

[tex]\tt Q=\dfrac{[A^+]^3}{[B^{+3}]}=\dfrac{0.5^3}{1.5.10^{-3}}=83.3[/tex]

E cell :

[tex]\tt E_{cell}=2-\dfrac{0.0592}{3}log~83.3\\\\E_{cell}=1.962~V[/tex]

Answer:

red blood cells

Explanation:

I'm not so sure though

Answer:

That is true!

Explanation: