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Photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation.

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Answer:I think it’s material chemistry

Explanation:

Answer:

Material chemistry.

Explanation:

Artificial bone and joint replacements is not environmental, it does not have anything to do with farming or such things, and physical chemistry has to do with chemical reactions which is not going on. This leaves materials chemistry.

Answer:

1.8 × 10² J

Explanation:

Step 1: Given data

Step 2: Calculate the amount of heat absorbed (q)

We will use the following expression.

q = m × c × ΔT

q = 20 g × 0.48 J/g.°C × (29 °C - 10 °C) = 1.8 × 10² J

Answer:

11.4

Explanation:

Density = Mass / Volume

Density = 35.4 / 3.11

Density = 11.38263666

As there are more number of digits after the decimal, you can round it to 3 significant figure.

Now, your value will be:

Density = 11.4

Answer:

5.4 mL of acid need to be added to 14.6 mL of water.

Explanation:

We can calculate how many mL of acid are needed by using the C₁V₁=C₂V₂ formula:

Then we calculate how many mL of water have to be added in order to reach 20.0 mL:

Thus, 5.4 mL of acid need to be added to 14.6 mL of water.

Answer: One with a pKa of 1.9

Hope this helps <3

P.S Fun Fact~~

There are only two words in the English language that have all five vowels in order: "abstemious" and "facetious."!

Answer:

Explanation:   Is there choises? H3PO4 / NaH2PO4 buffer with equal concentrations would form a buffer solution pH = 2.15

Answer:

Option A, The pH of the solution is 2.7 and the solution is acidic

Explanation:

As we know,

pH =  - log [H3O+]

Substituting the given values, we get

pH =  - log [2.1 x 10-3 M]

pH =  - (-2.678)

pH = 2.678 or 2.7

The solution is acidic as pH value is less than 7

Hence, option A is correct

Answer:

If you want to separate black grapes from the mixture of black and green grapes, then you will simply pick black grapes using your hands from the mixture. In this way you are actually using handpicking separation method.

Explanation:

Answer:

If reactant or product is removed, the equilibrium shifts to make more reactant or product, respectively, to make up for the loss.

If the reactant or product is removed, the equilibrium shifts to make more reactant or product, to make up for the loss.

Answer:

0.144 M

Explanation:

First we convert 0.307 g of KHP (potassium hydrogen phthalate, KHC₈H₄O₄) into moles, using its molar mass:

1 mol of KHP reacts with 1 mol of NaOH, that means that in 10.40 mL of the NaOH solution there were 0.0015 moles of NaOH.

Now we calculate the molarity of the NaOH solution:

Answer:

Hydrocyanic acid, HCN.

Explanation:

A buffer is defined as the aqueous mixture of a weak acid and its conjugate base. Or a weak base and its conjugate acid. In the problem, we have a solution of potassium cyanide. The conjugate acid of potassium cyanide is hydrocyanic acid. A weak acid with pKa = 9.89.

That means, to convert the solution into a buffer we must add:

Answer:

0.616 moles of Fe₂(CO₃)₃ are produced when 200 g of FeCl₃ react

b. 1.

Explanation:

The balanced reaction is:

First we convert 200 grams of FeCl₃ into moles, using its molar mass:

Then we convert 1.23 moles of FeCl₃ into moles of Fe₂(CO₃)₃, using the stoichiometric coefficients of the balanced reaction:

The closest answer would be option b. 1.

Explanation:

[tex]FeCl₃ + (NH₄)₂CO₃ → NH₄Cl + Fe₂(CO₃)₃[/tex]

first balance the chemical equation

[tex]2FeCl₃ + 3(NH₄)₂CO₃ → 6NH₄Cl + Fe₂(CO₃)₃[/tex]

2 mole. 3 mole. 6mole. 1mole

2*162g of FeCl₃ produce 236 g of Fe₂(CO₃)₃

200g of of FeCl₃

produce 236/(2*162)*20=145.68 g of Fe₂(CO₃)₃

1 mole of Fe₂(CO₃)₃=236g

145.68g of Fe₂(CO₃)=1/236*145.68=}0.61mole

closest answer is b 1

b.1mole(s) of iron (III) carbonate [Fe2CO3)3] is/are produced in the balanced equation

Answer:

11,1

Explanation:

-log(1.3x10^-11)

The pH of a solution with a hydrogen ion concentration of 1.3X10^-11 is -11.1. Therefore, option A is correct.

The potential of hydrogen ion concentration is referred to as pH. a way to gauge how basic or acidic a material is. The pH scale represents from 0 to 14.

A pH value of 7 is considered neutral on this scale, which implies it is neither acidic nor basic. It is more than acidic if the pH value is below seven, and more basic if the pH value is above seven.

The pH can control the presence of nutrients, biological processes, microbial activity, and chemical behaviour.

Given:

Hydrogen ion concentration = 1.3X10^-11

pH = -log [H+]

pH = -log(1.3x10^-11)

pH = -11.1

Thus,-11.1 is the pH of a solution with a hydrogen ion concentration of 1.3X10^-11, option A is correct.

To learn more about the pH, follow the link;

https://brainly.com/question/15289741

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Answer:

83.3 L

Explanation:

Step 1: Given data

Capacity of the wine barrel (V): 22.0 gal

Step 2: Calculate how many liters of wine can be held in the barrel

To calculate the number of liters of wine that can be held in the barrel, we need to convert 22.0 gal to liters. We will use the conversion factor 1 gal = 3.79 L.

22.0 gal × 3.79 L/1 gal = 83.3 L

The heat capacity of the metal is calculated using the formula:

What is temperature?

The temperature of a substance is the degree of hotness or coldness of that substance.

Temperature difference between substances enables heat flow.

Heat flows from hot to cold bodies.

In the given experiment, to determine the heat capacity of a metal, the temperature difference is obtained by substracting the initial and final temperatures.

The heat capacity of the metal is then calculated using the formula:

Learn more about heat capacity at: https://brainly.com/question/21406849

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Answer:

1.22 J/g.°C

Explanation:

Step 1: Given data

Step 2: Calculate the specific heat of the metal (c)

A metal absorbs heat and, as a consequence, its temperature increases. We can calculate its specific heat using the following expression.

c = Q / m × ΔT

c = 570.4 J / 17.5 g × 26.8 °C = 1.22 J/g.°C

Answer:

a - carbon is not toxic to living things

Explanation:

The reason carbon dating works is that the fresh carbon-14 gets mixed in with the rest of the carbon in the atmosphere and, since it's chemically identical to regular carbon, gets worked into whatever is presently absorbing atmospheric carbon

Answer:

option number 4. 'coral'

Explanation:

-

Answer:

C. Blood sugar increases b/c insulin lowers blood sugar when it rises too high

Explanation:

Insulin is highly needed by body to regular sugar levels (primarily to lower it when sugar levels rise up). I remember it like this "in" sulin means this hormones "pushes" the sugar inside the cells so that sugar level in the blood comes back to normal.

Therefore, if there is not enough insulin produced by pancreas, blood sugars will rise which can be fatal. That's why some diabetic patients take insulin shots to regulate their blood glucose levels.

Answer:

Explanation:

How many mols do you have?

1 mol = 6.02 * 10^23 atoms

x mol = 6.25 * 10 ^32 atoms

1/x = 6.02*10^23 / 6.25 * 10^32        Cross multiply

6.02 * 10^23 * x = 1 * 6.25 * 10^32    Divide by 6.02 * 10^23

x = 6.25 * 10*32/ 6.02 ^10^23

x = 1.038 * 10^9 mols which is quite large.

Find the number of grams. (Use the value for copper on your periodic table. I will just use an approximate number.)\

1 mol of copper = 63 grams.

1.038 * 10^9 mols of copper = x

1/1.038 * 10^9 = 63/x         Cross multiply

x = 1.038 * 10^9 * 63

x = 6.54 * 10^10 grams of copper.

Answer: Electrons are taken up by [tex]PbO_2[/tex] and they are lost by [tex]HCl[/tex]

Explanation:

Redox reaction is defined as the reaction in which oxidation and reduction take place simultaneously. It is also called the reaction where the exchange of electrons takes place.

An oxidation reaction is defined as the reaction in which a chemical species loses electrons takes place. In this reaction, the oxidation state of a substance gets increased.

A reduction reaction is defined as the reaction in which a chemical species gains electrons takes place. In this reaction, the oxidation state of a substance gets reduced.

For the given chemical reaction:

[tex]PbO_2+4HCl\rightarrow PbCl_2+Cl_2+2H_2O[/tex]

The half-reactions for this redox rection follows:

Oxidation half-reaction:  [tex]2HCl\rightarrow ClO_2 + 2e^-[/tex]

Reduction half-reaction:  [tex]PbO_2+2e^-\rightarrow PbCl_2[/tex]

Hence, electrons are taken up by [tex]PbO_2[/tex] and they are lost by [tex]HCl[/tex]

Answer:

Following are the solution to the given question:

Explanation:

Please find the matching in attached file.

During the electrolysis of Molten LiBr : Li is reduced and Br are oxidized .

Lithium Metal is produced at the Cathod during the electrolysis of Molten LiBR .

In the aquous LiBr : In aquous LiBr potential of Li is greater than the of water then Li is reduced to produce solid Li ion.  As well As aqueous LiF ( electrolysis)and Molten LiF electrolysis produce the gas.  

aqueous LiF: Oxygen gas.

Molten LiF : Flourine gas.  

Answer:. Dark purple

(b). Orange yellow

(c). Red

Explanation:

Answer:

Here is your Answer.......

Explanation:

The Watson and Crick's ball-and-stick model of DNA best illustrates the role of creativity in scientific discovery

Answer:

Explanation:

Short answer: Yes.

The coefficients may not be conserved, but mass always has to be. Take this equation as an example

2 Mg3P2 ===>   6Mg + P4

There is a 2 on the left side and 6 and 1 on the right. I hope you mean that the coefficient 2 is not equal to 7.

But let's look a little closer. You have to look at the molecular structure of the left and right side.

2Mg3P2 has 6 Mgs and 4 Ps on the left side.

6Mg is on the right. They are free standing.

P4    has 1 molecule consisting of 4 Ps.

Everything balances.

This is a terrific question to be asking. You need to understand the internal balance numbers vs the molecular ones on the out side.

That sounds like a bit of gobbledygook and it takes a bit of study.

2 Mg3P2 means that Mg3P2 is written twice.

Mg3P2 ==> "3 Mg2+   +  2P3+   and there is another one written the same way.

Mg3P2 ==> "3 Mg2+   +  2P3+  

Answer:

melting

its true believe it you sheep

Answer:

9460 kj

Explanation:

just did it