Calculate the number of molecules of carbon (IV) oxide
produced when 10g of CaCO3 is treated with 100cm of
0.2mol dm HCl. The equation of the reaction is
CaCO3(s) + 2HCl(aq) → CaCl2(aq) + H2O(1) + CO2(g)
ICa=40 (=12 O=161

Answer: The correct option is A) 8.97

Explanation:

To calculate the [tex]K_b[/tex] of a reaction, we use the equation:

[tex]K_a\times K_b=10^{-14}[/tex]

where,

[tex]K_a[/tex] = acid dissociation constant of acetic acid = [tex]1.86\times 10^{-5}[/tex]

[tex]K_b[/tex] = base dissociation constant

Putting values in above equation, we get:

[tex](1.86\times 10^{-5})\times K_b=10^{-14}\\\\K_b=\frac{10^{-14}}{1.86\times 10^{-5}}=5.37\times 10^{-10}[/tex]

To calculate the hydroxide ion concentration of conjugate base, we use the equation:

[tex][OH^-]=\sqrt{K_b\times \text{[Conjugate base]}}[/tex]

where,

[Conjugate base] = 0.10 M

Putting values in above equation, we get:

[tex][OH^-]=\sqrt{(5.37\times 10^{-10})\times 0.1}[/tex]

[tex][OH^-]=7.33\times 10^{-6}[/tex]

To calculate the pOH of the solution, we use the equation:

[tex]pOH=-\log [OH^-][/tex]

[tex]pOH=-\log (7.33\times 10^{-6})[/tex]

[tex]pOH=5.03[/tex]

To calculate the pH of the solution, we use the equation:

pH + pOH = 14

pH + 5.03 = 14

pH = (14 - 5.03) = 8.97

Hence, the correct option is A) 8.97

Answer:

Atomic Number. 15=phosphorus

Valency=3

So, Oxide=P203

Answer:

b. 0.27 M ammonia + 0.38 M ammonium nitrate.

Explanation:

Hello there!

In this case, according to the given information, it turns out possible for us to bear to mind the fact that buffest must be prepared by using either of the following pairs:

weak acid/conjugate base

weak base/conjugate acid

So that the pH might be set constant. In such a way, since a. shows two salts, c. a strong acid with a neutral base, d, shows two acids and e. a strong base with a neutral base, we infer the correct buffer is b. 0.27 M ammonia + 0.38 M ammonium nitrate because it has a weak base (ammonia) and its conjugate acid, ammonium.

Regards!

Complete Question:

A calorimeter measures the heat involved in reactions or other processes by measuring the ______ of the materials _____ the process. The calorimeter is _______ to prevent transfer of heat to outside the device.

Answer:

Temperature; surrounding; insulated.

Explanation:

A calorimeter can be defined as a scientific instrument or device designed and developed for measuring the heat involved in reactions or other processes, especially by taking the measurement of the temperature of the materials surrounding the process.

Basically, a calorimeter is insulated using materials with very high level of resistivity so as to prevent heat transfer to the outside of the device (calorimeter). Some of the components that make up a simple calorimeter are thermometer, an interior styrofoam cup, an exterior styrofoam cup, cover, etc.

Additionally, a calorie refers to the amount of heat required to raise the temperature of a gram of water by one degree Celsius (°C).

Answer:

Temperature; surrounding; insulated.

Explanation:

A calorimeter measures the heat involved in reactions or other processes by measuring the Temperature of the materials surrounding the process. The calorimeter is insulated to prevent the transfer of heat outside the device.

Answer: what are the choices?!.

Explanation:

Answer:

A. Wax drips down the side of a lot candle.

Explanation:

The chemical change from solid to liquid. This is a combustion reaction, so carbon dioxide gas and water vapour is also produced but you can't see them

Answer:

A. Wax drips down the side of a lot candle.

Explanation:

Answer:

482

Explanation:

Answer:

gamma rays > X-rays > ultraviolet radiation > visible light > infrared > radio waves.

Explanation:

Electromagnetic waves are those waves that require no material medium for propagation. They can travel through space and they all move at the speed of light.

Electromagnetic waves are composed of both electric and magnetic fields which are mutually at right angles to each other.

The order of decreasing energy of electromagnetic waves is;

gamma rays > X-rays > ultraviolet radiation > visible light > infrared > radio waves.

Answer:

The answer is "5.4".

Explanation:

[tex]BoH + HCL =BCL +H_2o \\\\At eq \\\\N_1V_1=N_2V_2 \\\\v_2=20 \ ml\\\\[BCL]=\frac{20 \times 0.08}{20+20}=0.04\\\\pH = \frac{1}{2} [pkw - pk_b - \log e]\\\\pk_b = 2 pH - Pkw + \Log C\\\\pK_b=5.4[/tex]

Answer:

2-ethyl-3-methylbut-2-ene

Explanation:

The whole idea of IUPAC nomenclature is to devise a universally accepted system of writing the name of a compound from its structure.

According to IUPAC nomenclature, the root of the compound is the longest carbon chain. The substituents are named in alphabetical order and in such a way as to give each one the lowest number. The position of the functional group is indicated accordingly.

For the compound in question, its correct IUPAC name is 2-ethyl-3-methylbut-2-ene.

Answer:

37.9% v/v

Explanation:

Since both the alcohol and solution are presumed to be liquid, this concentration can be expressed as a volume concentration (or % v/v):

volume concentration = volume of solute / volume of solution

[tex]\% v/v = 55/145= 0.379[/tex]

Chemistry and chemical reactions are not just limited to the laboratories but also the world around you.

Chemistry in Food Production:

Plants produce food for themselves through photosynthesis; which is a complex chemical reaction in itself. The chemical reaction that takes place in photosynthesis is the most common and vital chemical reaction. 

6 CO2 + 6 H2O + light → C 6H12O6 + 6 O2

Chemistry in Hygiene:

Right before you consume your food, you make it a point to wash your hands with soap. Isn’t it? The cleaning action of soap is based on its ability to act as an emulsifying agent. Soaps are fatty acids salts of sodium or potassium; produced by a chemical reaction called saponification. Soaps interact with the grease or oil molecule, which, in turn, results in a cleaner surface.

The Chemistry of an Onion:

Ever wondered why you shed tears while chopping an onion? This also happens because of the underlying chemistry concepts. As soon as you slice an onion, sulfenic acid is formed from amino acid sulfoxides. Sulfenic acid is responsible for the volatile gas, propanethiol S-oxide, that stimulates the production of tears in the eyes.

Chemistry in Baking:

Who does not like to eat fluffy freshly baked bread? Baking soda is an efficient leavening agent. The addition of baking soda to food items before cooking leads to the production of carbon dioxide (CO2); which causes the foods to rise. This whole process of rising of baked good is called chemical leavening.

Chemistry in Food Preservatives:

In case you ever read the ingredients on the bottle of ketchup, jams or pickles, you might be surprised to see a never-ending list of chemicals. What are they? These chemicals are called food preservatives; which delay the growth of microorganisms in foods. The chemical food preservatives not only prohibit the growth of bacteria, virus, fungi but also hinder the oxidation of fats, which is responsible for making the foods rancid. The most common chemical food preservatives are sodium benzoate, sorbic acid, potassium sorbate, calcium sorbate, sodium sorbate, propionic acid, and the salts of nitrous acid.

Chemistry in Digestion

The moment you put food in your mouth, a number of different chemical reactions start in your digestive tract. Saliva contains the enzyme amylase, which is responsible for breaking down carbohydrates, the stomach starts producing hydrochloric acid, the liver releases bile and the list of compounds released during digestion goes on. How do they work? All these enzymes undergo chemical reactions so that proper digestion, as well as assimilation of the food, occurs.

The Working of a Sunscreen

Before going out on a sunny day, you make it a point to wear sunscreen. Even the principle, behind the working of a sunscreen, has a chemistry background. The sunscreen uses a combination of organic and inorganic compounds to act as a filter for incoming ultraviolet rays. Sunblocks, on the other hand, scatter away UV light; so that it is unable to penetrate deep into the skin. Sunblocks contain complex chemical compounds like zinc oxide or titanium oxide, which prevent the UV rays to invade deeper into the skin.

Chemistry in Rust Formation

With time, your iron instruments start developing an orange-brown flaky coating called rust. The rusting of iron is a type of oxidation reaction. The atoms in the metal iron undergo oxidation and reduction; causing rusting. The formation of verdigris on copper and the tarnishing of silver are also the other everyday examples of chemical reactions. The chemical equation underlying rusting is:

Fe + O2 + H2O → Fe2O3. XH2O

Hope it helps.

Answer:

d,e

Explanation:

Answer:

mwlooy kagabi jal

64 JAHA VI PHÂN KAY

Answer:

30 grams of KNO3 can be dissolved.

Explanation:

Hello there!

In this case, since the solubility is defined as the maximum amount of solute that can be dissolved in a certain amount of solvent, usually 100 grams of water as function of the temperature, we will need to recall the graph for the solubility of KNO3 as shown on the attached file.

Thus, by identifying the curve for KNO3, we realize that at a temperature of 20 °C, the solubility is about 30 grams; which means 30 grams can be dissolved in 100 grams of water at 20 °C.

Regards!

Answer:

história phkfk

Explanation:

guiooupigjdytrss

Answer:

please mark as brainliest

Explanation:

The sun is shining on the shallow ocean water where the grasses and dugongs live. What is happening to the carbon in the water around the grasses and the dugongs? Is carbon moving into the water, moving out of the water, or both? Carbon is not moving into the water; it is only moving out of the water.

Answer:

electrovalent

NaCl

Lithium Carbonate

ammonium phosphate

aluminium floride

potassium hydride

covalent

methane

benzene

carbon iv oxide

hydro flouride

hydro chloride

Answer:

Platinum is especially good for this because it is unreactive, and does not produce a color in the flame which will mask the presence of other metals.

Hope this answer is right!

Answer:

Hey mate, here is your answer

1. Platinum doesn't impart any color to the flame.

2. It is not oxidised under the high temperature of the flame from a bunsen burner.

3. It is almost chemically inert. Even at high temperatures, it remains unattacked by free radicals / acid radicals.

Therefore, platinum wire is crucial for a flame test. Also, a platinum wire should be thoroughly cleaned before using it for a new flame test.

A platinum wire is cleaned by dipping it into concentrated HNO3 and then placing it in the non luminous part of the bunsen flame. Otherwise, the perviously tested radicals will impart color to the flame, which may cause confusion.

Explanation:

Hope it helps you

Answer and Explanation:

The reaction is in the gas phase, so the equilibrium constant is expressed in terms of the partial pressures (P) of the products and reactants, as follows:

[tex]Kp = \frac{P^{2}_{SO_{3} } }{P_{SO_{2}} ^{2}P_{O_{2}} }[/tex]

We have the following data:

P(SO₃) = 2.6 atm

P(O₂) = 0.43 atm

We need Kp for this reaction. We can assume that in Appendix 4 we found that Kp = 7 x 10²⁴.

Then, we introduce the data in the equilibrium constant expression to calculate the partial pressure f SO₂ (PSO₂), as follows:

[tex]P_{SO_{2} } = \sqrt{\frac{P_{SO_{3} } ^{2} }{Kp P_{O_{2} } } } = \sqrt{\frac{(2.6 atm)^{2} }{(7 x 10^{24)}(0.43 atm) } } = 1.5 x 10^{-12} atm[/tex]

Therefore, the partial pressure of SO₂ is 1.5 x 10⁻¹² atm (for the given Kp).

Answer:

531.6g

Explanation:

Total moles of glucose in this case is: 886/180= 4.922 (mole)

For every 1 mole glucose we get 6 mole water

-> Mole of water is: 4.922 * 6= 29.533 (mole)

weight of water is 18. Therefore, total weight of water that we will have from 886g of glucose are: 25.933*18= 531.6g

Answer:

The quantity of  heat required to raise the  temperature of 500 g of  iron by 2°C is 500 J.

Explanation:

Calorimetry is responsible for measuring the amount of heat generated or lost in certain physical or chemical processes.

The sensible heat of a body is the amount of heat received or transferred by a body when undergoing a temperature variation (Δt) without there being a change in physical state (solid, liquid or gaseous).

Its mathematical expression is the fundamental equation of calorimetry. This is:

Q = c * m * ΔT

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

In this  case:

Replacing:

Q= 500 [tex]\frac{J}{kg*C}[/tex] *0.500 kg*2 C

Solving:

Q= 500 J

The quantity of  heat required to raise the  temperature of 500 g of  iron by 2°C is 500 J.

Answer:

Empirical formula has a molar mass of 30.01g/mol and molecular formula is C₆H₁₂O₆

Explanation:

Molar mass of a molecule is the sum of the molar mass of each atom. In CH2O we have:

1C = 1*12.01g/mol = 12.01g/mol

2H = 2*1g/mol = 2g/mol

1O = 1*16g/mol = 16g/mol

Empirical formula of CH2O is:

12.01g/mol + 2g/mol + 16g/mol = 30.01g/mol

As the molecular compound has a molar mass of 180.0g/mol the molecular formula is:

180.0g/mol / 30.01g/mol = 6 times the empirical formula. That is:

Answer:

184.8 g

Explanation:

Step 1: Write the balanced thermochemical equation

C₈H₁₈(l) + 25/2 O₂(g) ⇒ 8 CO₂(g) + 9 H₂O(g)   ΔH°rxn = -5074.1 kJ

Step 2: Calculate the moles of octane required to produce 8210 kJ of heat

According to the thermochemical equation, 5074.1 kJ of heat are released per mole of octane consumed.

-8210 kJ × 1 mol C₈H₁₈/(-5074.1 kJ) = 1.618 mol

Step 3: Calculate the mass corresponding to 1.618 moles of octane

The molar mass of C₈H₁₈ is 114.23 g/mol.

1.618 mol × 114.23 g/mol = 184.8 g

1mol produces=5074.1KJ heat .

Moles produce 8210 KJ heat :-

Molar mass of Octane :-

Mass of Octane=

Answer:

As the temperature increases, the average kinetic energy increases as does the velocity of the gas particles hitting the walls of the container. The force exerted by the particles per unit of area on the container is the pressure, so as the temperature increases the pressure must also increase.

I hope this will help you if not soo sorry :)

Answer:

The netto reaction equation is:

2 OH- + 2H+ = 2 H2O  

So the answer is 2 moles.