in an experiment a piece of magnesium ribbon was cleaned with steel wool 2.4g of the clean ribbon was placed in a crucible and completely... In an experiment a piece of magnesium ribbon was cleaned with steel wool 2.4g of the clean ribbon was placed in a crucible and completely burnt in oxygen.after cooling the product weighted 4.0g. (a)explain why it was necessary to clean the magnesium ribbon? (b)what observation was made in the crucible after burning? (c)why was there an increase in mass? (d)write the equation for reaction which took place in the crucible? (e)the product in the crucible was shaken with water and filtered.​

Answers

Answer 1

(a) It was necessary to clean the magnesium ribbon in order to remove any impurities or contaminants that might be present on the surface of the ribbon. These impurities could interfere with the burning process or alter the final products of the reaction.

(b) After burning, it is likely that an ash or residue was observed in the crucible.

(c) The increase in mass may be due to the production of new products during the burning process. These products may include magnesium oxide, which is a white solid, or other compounds formed through the reaction of magnesium with oxygen.

(d) The equation for the reaction that took place in the crucible is:

2Mg + O2 -> 2MgO

(e) When the product in the crucible is shaken with water, it is likely that any soluble products, such as magnesium hydroxide, will dissolve in the water. The remaining solid material can then be filtered out, leaving a solution containing the dissolved products.

Answer 2
Final answer:

The magnesium ribbon was cleaned to remove any impurities that could affect the reaction. After burning magnesium in oxygen, the resulting product is magnesium oxide, and the mass increases because the magnesium combines with the oxygen. The reaction equation is 2Mg + O2 -> 2MgO.

Explanation:

(a) It was necessary to clean the magnesium ribbon with steel wool to remove any surface oxidation or impurities that could affect the reaction.
(b) After burning, an observation that could be made in the crucible would be a white ash-like substance, which is magnesium oxide.
(c) There was an increase in mass because when magnesium reacts with oxygen, it gains mass as it combines with the oxygen to form magnesium oxide.
(d) The equation for the reaction is: 2Mg + O2 -> 2MgO
(e) When the product in the crucible was shaken with water and filtered, this procedure would typically be used to isolate the product from any remaining unreacted magnesium or other reaction by-products.

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Related Questions

A mixture of gases contains oxygen, nitrogen, and hydrogen at 0 degrees Celsius. The partial pressure of the oxygen gas is 20 kPa, the partial pressure of nitrogen gas is 40 kPa, and the partial pressure of hydrogen gas is 14 kPa. What is the total pressure exerted

Answers

The total pressure exerted by the gas mixture is 74 kPa.

What is hydrogen?

Hydrogen is an odorless, colorless, and tasteless gas that is the most abundant element in the universe. It is the lightest of all elements and is a component of many compounds, such as water and hydrocarbons. Hydrogen has the highest energy content of any common fuel, making it an attractive energy source. Additionally, it is utilised in the manufacture of fertiliser, polymers, and pharmaceuticals as well as a propellant.

This is calculated by adding up the partial pressures of each individual gas in the mixture, which in this case is 20 kPa for oxygen, 40 kPa for nitrogen, and 14 kPa for hydrogen. 20 + 40 + 14 = 74

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A compound is found to contain 15.94 % boron and 84.06 % fluorine by mass. What is the empirical formula for this compound

Answers

The empirical formula of the compound is BF3.

The empirical formula of a compound is the simplest whole-number ratio of atoms that represents the compound's composition. To determine the empirical formula of a compound, we need to determine the number of moles of each element present and then simplify the ratio of moles to the smallest whole-number ratio.

First, we can use the percentages of boron and fluorine to find the number of grams of each element present in 100 grams of the compound:

15.94 g boron / 100 g compound

84.06 g fluorine / 100 g compound

Next, we can convert the number of grams of each element to moles using the molar masses of boron and fluorine:

15.94 g B / (10.81 g/mol) = 1.48 mol B

84.06 g F / (18.99 g/mol) = 4.44 mol F

To find the empirical formula, we divide the number of moles of each element by the lowest number of moles:

1.48 mol B / 1.48 mol B = 1.00

4.44 mol F / 1.48 mol B = 3.00

So the empirical formula of the compound is BF3.

It's important to note that this is the empirical formula, and the actual formula of the compound could be a multiple of this depending on the chemical structure of the compound.

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In a given reaction, the rate may be expressed as either rate What must be true about X or Y if the reaction is proceeding in the forward direction

Answers

In a given reaction, the rate may be expressed as either the rate of formation of a product (X) or the rate of consumption of a reactant (Y). If the reaction is proceeding in the forward direction, the rate of formation of the product (X) will be positive and the rate of consumption of the reactant (Y) will be negative.

This means that X is being produced at a faster rate than it is being consumed and Y is being consumed at a faster rate than it is being produced.

Alternatively, if the reaction proceeds in the opposite direction, the rate of formation of products (X) is negative and the rate of consumption of reactants (Y) is positive. This means that X is consumed faster than it is produced, and Y is produced faster than it is consumed.

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Why is it that some materials made up of entirely nonmetal atoms are soluble in water while some are not

Answers

some materials made up of entirely nonmetal atoms are soluble in water while some are not Due to different combinations of pairs created, which might either dissolve extremely well, or not dissolve whatsoever

The solubility of a substance in water depends on the nature of the chemical interactions between the substance and the water molecules. Some materials made up of entirely nonmetal atoms are soluble in water because they can form hydrogen bonds with the water molecules. These materials are called polar solvents and are typically composed of polar molecules, like those found in many organic compounds. For example, ethanol (C2H5OH) is a polar solvent that is composed of entirely nonmetal atoms and is soluble in water because it can form hydrogen bonds with the water molecules.On the other hand, some materials composed of entirely nonmetal atoms are not soluble in water because they do not form hydrogen bonds with the water molecules. These materials are called non-polar solvents and are typically composed of non-polar molecules, like those found in many hydrocarbons.

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different between ionic and metallic bond ​

Answers

Answer:

Whereas ionic bonds join metals to non-metals, metallic bonding joins a bulk of metal atoms.

Explanation:

hope this helps

Diatomic elements are important. what makes them different from other elemental substances?

Answers

Diatomic elements are different from other elemental substances because they consist of two atoms of the same element bound together.

What are Diatomic elements?

Diatomic elements are elements that generally exist as molecules composed of two atoms of the same element. The seven elements that exist as diatomic molecules are hydrogen (H2), oxygen (O2), nitrogen (N2), fluorine (F2), chlorine (Cl2), bromine (Br2), and iodine (I2).

The two atoms form a covalent bond, meaning that each atom shares its outermost electrons with the other atom. This creates a strong bond between the two atoms, making the diatomic element more stable and less reactive than other elemental substances.

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Container A holds 747 mL747 mL of ideal gas at 2.90 bar2.90 bar . Container B holds 119 mL119 mL of ideal gas at 4.30 bar4.30 bar . If the gases are allowed to mix together, what is the partial pressure of each gas in the total volume

Answers

the partial pressure of gas A in the total volume is 3.57 bar, and the partial pressure of gas B in the total volume is 0.70 bar.

When the gases are allowed to mix together, the total pressure of the mixture is equal to the sum of the partial pressures of each gas. The partial pressure of each gas is equal to the product of the total pressure and the mole fraction of that gas. To find the mole fraction of each gas, we first need to find the number of moles of each gas. The number of moles of gas in container A is given by PV/RT where P is the pressure, V is the volume, R is the ideal gas constant and T is the temperature.

n_A = (2.90 bar * 747 mL) / (8.314 J/molK * (273.15 + 23)) = 0.0295 mol

The number of moles of gas in container B is given by PV/RT

n_B = (4.30 bar * 119 mL) / (8.314 J/molK * (273.15 + 23)) = 0.0045 mol

The total number of moles of gas in the mixture is the sum of the number of moles of gas in container A and container B.

n_total = n_A + n_B = 0.0295 mol + 0.0045 mol = 0.0340 mol

The mole fraction of gas A in the mixture is the number of moles of gas A divided by the total number of moles of gas.

x_A = n_A / n_total = 0.0295 mol / 0.0340 mol = 0.8735

The mole fraction of gas B is

x_B = n_B / n_total = 0.0045 mol / 0.0340 mol = 0.1324

The partial pressure of gas A is equal to the total pressure multiplied by the mole fraction of gas A.

P_A = (0.8735) * (2.90 bar + 4.30 bar) = 3.57 bar. The partial pressure of gas B is equal to the total pressure multiplied by the mole fraction of gas B. P_B = (0.1324) * (2.90 bar + 4.30 bar) = 0.70 bar

So the partial pressure of gas A in the total volume is 3.57 bar, and the partial pressure of gas B in the total volume is 0.70 bar.

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How do we measure the distance?

Answers

We measure the distance through many objects like; Radar, Parallax, Capheids, Redshift and Hubble's Law etc.

Distance is termed as the size or magnitude of the displacement between two positions.  

There are several ways to measure the distance in terms of science. Firstly, Radar: It is used to measure the distance in our solar system and to measuring the distances to nearby the stars are Parallax. Whereas, Capheids is also used to measuring the distance in our galaxy and to nearby the galaxies. However, Supernovae will measuring the distances to other galaxies and the last one is Redshift and Hubble's Law it is used to measuring the distances to objects which is far away.

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In terms of binding energy per nucleon, what element divides fission and fusion processes? O He
O U O Fe
O C
O H

Answers

Fe which is Iron is the element that distinguishes between fission and fusion processes in terms of binding energy per nucleon.

Since the negatively charged electrons are held in place by the electrostatic pull of the positively charged nucleus, the electron binding energy is the lowest energy needed to remove an electron from an atom. Fe element distinguishes between fission and fusion processes in terms of binding energy per nucleon. In particle physics, the term "binding energy" describes the energy an atom receives from electromagnetic interaction as well as the quantity of energy needed to break an atom down into free nucleons.

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What is the mass in grams of 1.56 moles of aspartame?

Answers

459.1 g of aspartame has a 1.56 moles of aspartame.

Artificial sweetener aspartame is potent and low in calories. About 200 times sweeter than sugar, it is a white, odourless powder. It is legal to use in Europe as a tabletop sweetener, an energy-reducing food ingredient in beverages, desserts, and sweets, dairy products, chewing gum, and other foods.

Aspartame is a dipeptide that is created through the formal condensation of the amino group of methyl L-phenylalaninate with the alpha-carboxy group of L-aspartic acid.

Here, aspartame has 1.56 moles.

Molar mass of aspartame = 294.40 g/mol

So, Number of moles of aspartame = [tex]\frac{Given Mass}{Molar Mass}[/tex]

Mass of aspartame = Number of moles × Molar mass

or, mass = 1.56 × 294.3

or, mass = 459.1 g

Hence, Mass of aspartame of 1.56 moles of aspartame is 459.1 g.

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In what part of this system are the two energy outputs found?

Answers

The part of the system that has two outputs of energy is the bulb.

What is the energy transformation?

We would have to recall that on the basis of the first law of thermodynamics, it can be said that energy can not be created nor destroyed but that energy would have to be converted from one form to the other.

In this case, we can see that as the boy is cycling, there is the conversion of the mechanical energy of the boy to the heat and the light energy of the bulb as shown. These are the outputs referred to above.

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How many moles are in 50 grams?

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3.125 moles of oxygen are present in 50 g.

A mole is the volume of a substance that contains 6.022 X 1023 of the substance's particles, atoms, ions, molecules, etc. A mole is a unit for counting molecules, ions, or atoms. Divide the given mass of an element by its molar mass to find the number of moles in that quantity.

The atomic weight of an element, or its relative atomic mass, on the periodic table, expressed in g/mol, is its molecular mass.

The molar mass of oxygen is 16 g/mol, and there are 3.125 moles in a given amount of mass and molar mass.

Consequently, 3.125 moles of oxygen are present in 50 g.

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Calculate the mass of water needed to prepare 45 g of salt solution if the salt content in the solution is 12%.​

Answers

The mass of water needed to prepare 45 g of salt solution if the salt content in the solution is 12% is 330g.

The solute is the thing that needs to dissolve, and the solvent is the thing that needs to dissolve it. With a wide variety of solutes and solvents, solutions can be created. We are aware of a wide range of solutions.

Given,

Mass of the salt solution (Solute) = 45g

salt content in the solution = 12%

Let Mass of water = x

Total mass of solution = 45 + x

Concentration of solution = Mass of solute / Mass of Solution × 100

12 = 45 / 45 + x × 100

⇒ 12/100 = 45 / 45 + x

⇒ 0.12 = 45 / 45 + x

⇒ 0.12 (45 + x) = 45

⇒ 5.4 + 0.12x = 45

⇒ 0.12x = 45 - 5.4

x = 330g

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The piston in the engine of a car converts the energy released by octane combustion into mechanical work that turns the crankshaft. Some of the energy is lost to the environment as heat. What are the appropriate signs on q and w for this process

Answers

Thermal energy is transformed into kinetic energy that is, the energy of a moving object in this example, the moving piston by the engine. So, the sign of heat is negative and work done is negative.

A complicated device known as a combustion engine consumes fuel to produce thermal energy, which is subsequently used to drive tasks. In a car, the engine is responsible for generating the kinetic energy needed to turn the wheels. An internal combustion engine is the type of combustion engine used in automobiles. Internal-combustion engines are those found in gasoline or diesel-powered automobiles. Such an engine obtains its power from the heat produced during the combustion of the working fluids that have not yet reacted, the oxidizer-fuel mixture. As the heat is released to convert into the kinetic energy the sign of heat is negative and the sign of work done by the internal combustion of vehicles is negative.

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If 25.0 mL of 15M nitric acid is diluted to 125 mL, what is the concentration of the new solution?

Answers

Answer:2.5M

Explanation:

let the number of moles = x

x/0.025L =15

x= 15*0.025 = 0.375 moles

the concentration of the new solution = moles / volume =

0.375 / (0.025+0.125) = 2.5M

Does carbon-14 or nitrogen-14 have more neutrons?

Answers

Carbon 14 would have more neutron than nitrogen 14

The atomic number of an atom, as is generally known, represents the total number of protons that make up the nucleus of that atom. We are aware that the mass number of carbon is 14, and that its atomic number is 6. It is well-known that protons and neutrons combine to form mass. As a result, there will be = 14 - 6 = 8 neutrons.

while he mass number of nitrogen is 14, and that its atomic number is 7. It is well-known that protons and neutrons combine to form mass. As a result, there will be = 14 - 7 = 7 neutrons.

Therefore, Carbon 14 would have more neutron than nitrogen 14

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What is the relationship between CO2 levels and sea levels?

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The relationship between the CO₂ and the sea levels is the carbon dioxide is higher about 10 % at  deep ocean than the surface.

This  warms world due to the greenhouse gases that included the carbon dioxide , the water  heat up and it expands due to which the sea level rises.  if we remove the extra heat from the ocean that caused by the short lived gases , it lowers the sea levels and this process is very slow.

The carbon dioxide that dissolves in the ocean will cause the sea water to be acidify. this will harmful for the shellfish and the corals.

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The extended structure of sodium chloride (NaCl) is shown.


Which of the following describes the configuration of Layer 4 of the sodium chloride crystal?

OPTIONS
A
It will be identical in all of its characteristics to Layer 1.

B

It will contain 4 atoms of chlorine and 5 atoms of sodium.

C

It will have chlorine atoms in all four of its corners.


D
It will have sodium that are bonded only to other sodium atoms.

Answers

Sodium chloride crystal will contain 4 atoms of chlorine and 5 atoms of sodium. Therefore, option B is correct.

What is sodium chloride?

In sodium chloride, each ion is usually surrounded by 6 ions of the opposite charge. The surrounding ions are positioned at the vertices of a regular octahedron.

In the language of close-packing, the larger chloride ions are arranged in a cubic array whereas the smaller sodium ions fill all the cubic gaps between them.

The basic structure is commonly known as the halite or rock-salt crystal structure. It can be represented as a face-centered cubic lattice with a two-atom basis or as two face centered cubic lattices. The one atom is located at lattice point, and the second atom is located halfway between lattice points along edge of the fcc unit cell.

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select all that apply. please help! i will mark you brainliest

Answers

Kinetic energy increases as mass increases

The shape of the mass vs energy graph shows a linear relationship

When we double the mass, we double the energy.

Interpreting a graph

The graph shown in the image is a plot of the kinetic energy of objects on the y-axis and the mass of the objects on the x-axis.

The graph is a straight line. This shows that there is a linear relationship between the two parameters - the kinetic energy and mass of objects. Thus, the kinetic energy increases as mass of objects increases, and decreases as mass of objects increases.

From the graph, when the mass of objects are doubled, there is also a double in the amount of the kinetic energy of objects.

In summary, the graph shows that:

Kinetic energy increases as mass increasesThe shape of the mass vs energy graph shows a linear relationshipWhen we double the mass, we double the energy.

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Liquid hexane CH3CH24CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 7.76 g of hexane is mixed with 34. g of oxygen. Calculate the minimum mass of hexane that could be left over by the chemical reaction. Round your answer to 2 significant digits.

Answers

the minimum mass of hexane that could be left over by the chemical reaction is 17.2 grams of.

Hexane, a non-polar solvent having a boiling point of 68 degrees Celsius, is the one used to extract the oil from rice bran to produce rice bran oil (RBO). The International System of Units uses the mole (symbol: mol) as the unit of material quantity. How many elementary entities of a particular substance are present in an object or sample is determined by the quantity of that material.

Hexane moles equal 29/86=0.34

41.3/32 = 1.30 moles of oxygen

One mole of hexane takes 9.5 moles of oxygen, as shown by the reaction.

In this case, oxygen is the limiting reagent.

Consumption of moles of hexane is 1.30/9=0.144

Hexane remaining in moles is equal to 0.20 to 0.34 moles.

Hexane mass remaining = 0.2*86=17.2 grams.

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15) Lidocaine 2 gm/500 mL D5W is ordered to run at 3.5 mg/min. At what rate should the IV pump be set

Answers

Ordered to run at 3.5 mg/min is a dose of lidocaine 2 g/500 mL D5W. The IV pump should be set at a rate of 52.5 mL per hour.

Given 1mg/min = 60mg/hour

Then 3.5 mg/min = 3.5 x 60 mg/hour = 210mg/hour

Lidocaine is 2gm/500mL = 2000mg/500mL

If you only need to calculate the infusion rate, or the amount of medication to infuse per hour, you can do it by taking the entire volume in mL and dividing it by the total number of hours the medication is supposed to be infused over. This will give you the rate in mL per hour.

Then the flow of rate = 210mg/hour / 2000mg/500mL = 210x500/2000 = 52.5mL/hour.

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How long will it take Caroline to travel 45 miles if she is traveling 37mph (miles per hour)?

Answers

In the given question,It will take Caroline 1.2 hours  to travel 45 miles if she is traveling 37 mph (miles per hour).

As we know the velocity formula:

v = d/t

Where

V is velocity, d is distance and t is time.

as given in the question

distance = 45 miles

velocity = 37 mph

To find time t,

put the values in the formula:

t = d/v

t = 45/37

t = 1.2 hours

It will take Caroline 1.2 hours  to travel 45 miles if she is traveling 37 mph (miles per hour).

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Which of the following properties can be used to describe both the particle model of light and the wave model of light

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An absolutely interesting occurrence is light. Despite the fact that it is well recognized that light is an electromagnetic, it is frequently more practical to characterise or characterize light in other ways than only as a wave.

For instance, light is frequently depicted as anything other than a wave in spectroscopy and fundamental physics.

Similar to how we replicate oceans moving through water, the Wave Model illustrates how light propagates. Colors can be explained using the Wave Model by including information about wavelength.

The Light Wave Model. Similar to how we simulate ocean waves moving across water, the Wave Model illustrates how light propagates. We can explain qualities of light by imagining it to be an oscillating wave.

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Which of the following answer choices would BEST describe Marco Polo's reaction when he saw the Chinese using coal

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The majority of Europeans at the time had never heard of coal, which Marco Polo described as "black stones...which burn like logs."

Initially, charcoal was utilized in the production process, which caused extensive deforestation in northern China. However, coal had fully replaced charcoal by the end of the 11th century.

They do indeed have an abundance of firewood. However, due to the massive population and the large number of bathhouses and baths that are continually being heated, it would be impossible to supply enough firewood, as everyone takes a bath at least three times each week, and in the winter, if they can, every day. Since every man of rank and means has a bathroom of his own at home, the abundance and low cost of these stones result in significant wood savings.

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Place the following molecules in order of decreasing bond angle: NH3, CO2, CCl4, OF2
O CO2 > CCl4 > NH3 > OF2
O NH3 > CO2 > CCl4 > OF2
O CO2 > CCl4 > OF2 > NH3
O CCl4 > CO2 > OF2 > NH3
O OF2 > NH3 > CCl4 > CO2

Answers

The order of decreasing bond angle for the given molecules is :

O OF2 > NH3 > CCl4 > CO2

In molecules with a central atom, the bond angle is determined by the electron pair-bond pair repulsion. The bond angle decreases as the number of electron pair-bond pair increases. In OF2 the central atom is O, and it has 2 lone pairs and 2 single bonds, the bond angle is expected to be smaller than in the other molecules.In NH3, the central atom is N, and it has 3 single bonds and 1 lone pair, the bond angle is expected to be larger than in OF2 but smaller than in CO2 and CCl4. In CO2 and CCl4, the central atoms are C and Cl respectively, and they have 4 single bonds and no lone pairs, the bond angle is expected to be larger than in NH3, but smaller than in OF2.

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What is the density (using proper sig figs) of a rock with a volume of 6.7 mL and a mass of 12.34 grams?

Answers

Density is an intensive property as it does not depend on the quantity of the substances Whereas mass and volume are extensive property. Therefore, the density of a rock with a volume of 6.7 mL and a mass of 12.34 grams is 1.841g/ml.

What is density?

Density tells about the compactness of the substances, how much dense is the substances in other words. Object that is more denser than water they just sink in the water.

Mathematically,

Density of rock = Mass of the rock ÷volume marked on the graduated cylinder

volume of rock= 6.7 mL

mass of rock= 12.34 grams

Substituting all the values in above formula, we get

Density of rock=  12.34 grams÷6.7 mL

                           =1.841g/ml

Therefore, the density of a rock with a volume of 6.7 mL and a mass of 12.34 grams is 1.841g/ml.

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2CuO(s)+NO(g)→Cu2O(s)+NO2(g)
Express your answer using three significant figures.
ΔHrxn∘ =

Answers

ΔHrxn∘ = -144 kj / mol is the Standard Enthalpy of the reaction.  It is the sum of the individual enthalpies of the reactants subtracted from the sum of enthalpies of the products.  

2CuO(s)+NO(g) → Cu2O(s)+NO2(g)

[tex]Cu_{2}O[/tex] → 2[tex]Cu[/tex]  +  1/2 [tex]O_{2}[/tex]                                                        eqn 1

ΔH1 =  [tex]Cu_{2}O[/tex]  -  2 Cu - 1/2 [tex]O_{2}[/tex]

ΔH1 = -168.6 kj / mol  

2[tex]NO[/tex] + [tex]O_{2}[/tex] → [tex]2NO_{2}[/tex]                                                              eqn 2

ΔH2 = 2 [tex]NO[/tex]  +  [tex]O_{2}[/tex]   -  [tex]2NO_{2}[/tex]

ΔH2 = -114.1 kj / mol  

[tex]CuO[/tex] → [tex]Cu[/tex]  +  [tex]1/2 O_{2}[/tex]                                                            eqn 3

ΔH3 = Cuo - Cu -  [tex]1/2 O_{2}[/tex]

ΔH3=  157.3 kj / mol  

1/2 eqn 2    +          2  eqn 3    -  eqn 1

Δ H= -57.05 + 78.65 -168.6

ΔH= -144 kj / mol

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How do you most effectively increase the buffering capacity of a pH 4.9 buffer containing acetate (pKa 4.76)

Answers

A conjugate base solution with a pH between 8 and 10 has little buffer capacity, however at higher pHs, the strong base's presence begins to matter more.

Because of the large concentration of H + cations, a pure acetic acid solution with a pH below 3 already has a pH that is resistant to changes. This is because the concentration of the capacity is so high that it is unaffected by changes in the equilibrium of the solution brought on by the concentration of other ions. Why is a buffer more effective if its pKa is close to the pH? Why does a buffer function best when pH and pKa are equal? Why does increasing the pH by a basic or an acid.

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Please help with these 10 questions!! Show all work!! Will give brainliest!! :)

Answers

Carbon Dioxide: CO2

Formula: C + O2

15.0 moles of CO2 contains (15.0 moles CO2) x (1 mole C / 1 mole CO2) = 15.0 moles of C

Carbon Dioxide: CO2

Formula: C + O2

15.0 moles of CO2 contains (15.0 moles CO2) x (2 moles O / 1 mole CO2) = 30.0 moles of O

Calcium Chloride: CaCl2

Formula: Ca + 2Cl

23.0 moles of CaCl2 contains (23.0 moles CaCl2) x (1 mole Cl / 2 moles Cl) = 11.5 moles of Cl

Sulfur Dioxide: SO2

Formula: S + O2

295.0 grams of SO2 contains (295.0 grams SO2) x (1 mole S / 64.066 grams) = 4.6 moles of S

Potassium Sulfate: K2SO4

Formula: 2K + S + 4O

295.0 grams of K2SO4 contains (295.0 grams K2SO4) x (1 mole S / 174.259 grams) = 1.69 moles of S

Iron: Fe

Formula: Fe

565.0 grams of Fe contains (565.0 grams Fe) x (1 mole Fe / 55.845 grams) = 10.15 moles of Fe

metallic elements

SO2 is a covalent compound. It consists of one sulfur atom and two oxygen atoms joined together by covalent bonds, which are strong chemical bonds where electrons are shared between atoms.

H

|

O-H

A water molecule is polar because the electrons are not shared equally between the oxygen and hydrogen atoms. Oxygen is more electronegative than hydrogen, so it pulls the electrons closer to itself, creating a partial negative charge on the oxygen side of the molecule and a partial positive charge on the hydrogen side. This causes the molecule to have a dipole moment and makes the molecule polar.

NH3 (Ammonia) - the molecule is a pyramidal shape, which means that the Nitrogen is at the center and the three hydrogen atoms are located at the three corners of a pyramid.

H2O (Water) - the molecule is a V-shape, this shape is determined by the angle between the two bonding pairs and the two non-bonding pairs of electrons.

CH4 (Methane) - the molecule is tetrahedral shape, the carbon is in the center, and the four hydrogen atoms surround the carbon in a tetrahedral arrangement.

A color change

The formation of a precipitate

The evolution of a gas

A change in temperature

Uday Tahlan

Warm air rises because:

A.) It is made of helium

B.) As it warms the particles spread out making it less dense

C.) As it warms the particles get closer together making it more dense

D.) Air always moves towards the sun or moon due to gravity

Answers

As the air gets warmer it rises because,  particles spread out making it less dense. The diffusing capability of gas molecules make it possible.

What is intermolecular forces ?

Intermolecular force are the force that keep the particles of a substance binded together. Gaseous molecule easily diffuse in air , since the intermolecular attraction is very less in them.

In solid state molecules are densely packed and difficult to move apart. In liquid state , particles have some space to move and in gases molecules are far apart due to less intermolecular force.

As the gas molecules in air absorbs heat energy, they overcome all the intermolecular forces and will spread out in the air. Thus, they rises above over a temperature gradient.

Find more on intermolecular force:

https://brainly.com/question/9007693

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