A 13.00 g sample of a compound contains 4.15 g potassium (k), 3.76 g chlorine (cl), and oxygen (o). calculate the empirical formula.

Answers

Answer 1

To solve this problem, let us all convert the mass of each element into number of moles using the formula:

moles = mass / molar mass

Where,

molar mass K = 39.10 g / mol

molar mass Cl = 35.45 g / mol

molar mass O = 16 g / mol

and mass O = 13 g – 4.15 g – 3.76 g  = 5.09 g

 

moles K = 4.15 g / (39.10 g / mol) = 0.106 mol

moles Cl = 3.76 g / (35.45 g / mol) = 0.106 mol

moles O = 5.09 g / (16 g / mol) = 0.318 mol

 

The ratio becomes:

0.106 K: 0.106 Cl: 0.318 O

We divide all numbers with the smallest number, in this case 0.106. This becomes:

K: Cl: 3O

 

Therefore the empirical formula is:

[tex] KClO_{3} [/tex]


Related Questions

How many kilowatt-hours of electricity are used to produce 4.50 kg of magnesium in the electrolysis of molten mgcl2 with an applied emf of 5.00 v?

Answers

First, we need to determine the half reaction of magnesium. It would be expressed as:

Mg2+ + 2e- = Mg

Given the mass of magnesium metal that is produced, we calculate the total charge of the electrolysis by the relations we can get from the half reaction. We do as follows:

4.50 kg Mg ( 1000 g / 1 kg ) ( 1 mol / 24.305 g ) ( 2 mol e- / 1 mol Mg ) ( 96500 C / 1 mol e- ) = 35733388.2 C

We are given the applied EMF in units of V. This value is equal to J/C. So, 5 V is equal to 5 J/C.

35733388.2 C (5 J/C) = 178666941 J
178666941 J ( 1 kW-h / 3.6x10^6 J ) = 49.63 kW-h

The kilowatt-hours of electricity are used to produce 4.50 kg of magnesium in the electrolysis of molten MgCl₂ with an applied emf of 5.00 v is 49.63 kW-h. It can be find by knowing the half reaction of magnesium.

What is Half Reaction ?

A half reaction is either the oxidation or reduction reaction component of a redox reaction.

Let's determine the half reaction of magnesium ;

Mg²⁺ + 2e- => Mg

Given the mass of magnesium metal that is produced, we calculate the total charge of the electrolysis by the relations we can get from the half reaction. We do as follows :

4.50 kg Mg ( 1000 g / 1 kg ) ( 1 mol / 24.305 g ) ( 2 mol e- / 1 mol Mg ) (96500 C / 1 mol e-) = 35733388.2 C

We are given the applied EMF in units of V. This value is equal to J/C. So, 5 V is equal to 5 J/C.

35733388.2 C (5 J/C) = 178666941 J

178666941 J ( 1 kW-h / 3.6x10^6 J ) = 49.63 kW-h

Hence, The kilowatt-hours of electricity are used to produce 4.50 kg of magnesium in the electrolysis of molten MgCl₂ with an applied emf of 5.00 v is 49.63 kW-h.

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How does fluorine (F) differ from iodine (I)?

Answers

at room temp, iodine is a solid while fluorine is a gas. (hope that helps!)

Give the name of the element that is a member of the alkali metal family whose most stable ion contains 2 electrons.

Answers

lithium

Li → Li⁺ + e⁻

Li 1s²2s¹ → Li⁺ 1s² + e⁻

The name of the element that is a member of the alkali metal family whose most stable ion contains 2 electrons is "Ba (barium).

What is element?

A pure substance made up entirely of atoms with almost the identical count of protons in respective nuclei was known as an element.

It is known that Ba element can form +2 oxidation state very easily which belongs to the group 1.

Therefore, the name of the element that is a member of the alkali metal family whose most stable ion contains 2 electrons is "Ba (barium).

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Which alkane is the isomer of butane called 2-methylpropane?

Answers

The isomer of butane called 2-methylpropane is known as isobutane. It has a chemical formula written C4H10 and is known as the simplest alkane having a tertiary carbon. It was used as a refrigerant and known as R-600a. However, towards the end of 2009, it was suggested that the use of such in refrigerators is dangerous. A number of explosion of refrigerators were reported and it was suspected that the cause is the leaking of isobutane and being ignited by the electrical system. At that point, the use of such as refrigerant was discouraged and was being replace by safer refrigerants. Isobutane is also being used as a raw material in the petrochemical industry like in the synthesis of the fuel isooctane. 

Answer:

Its B

Explanation:

Write the balanced chemical equations for the complete combustion of acetic acid (ch3cooh), the main active ingredient in vinegar.

Answers

The balanced chemical equation for the complete combustion of acetic acid (CH3COOH) is CH3COOH(l) + 2 O2(g)
ightarrow 2 CO2(g) + 2 H2O(l), which indicates the complete conversion of acetic acid to carbon dioxide and water.

Balanced Chemical Equation for the Combustion of Acetic Acid

The complete combustion of acetic acid (CH3COOH) involves its reaction with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O) as products. The balanced chemical equation is as follows:

CH3COOH(l) + 2 O2(g)
ightarrow 2 CO2(g) + 2 H2O(l)

This reaction shows the acetic acid undergoing complete combustion in the presence of excess oxygen, ensuring all carbon is converted to carbon dioxide and all hydrogen to water, with no other products formed.

Ionization of Acetic Acid

Additionally, acetic acid can ionize in solution:

CH3COOH(aq)
ightleftharpoons H+(aq) + CH3COO
-(aq)

Because acetic acid is a weak acid, this ionization is not complete, and an equilibrium is established, favoring the reactant side. This illustrates the weak acidic nature of acetic acid in an aqueous solution.

The chemical equation that is balanced to allow acetic acid to burn completely ([tex]CH_3COOH[/tex]) is [tex]\text{CH}_3\text{COOH} + 2 \text{O}_2 \rightarrow 2 \text{CO}_2 + 2 \text{H}_2\text{O}[/tex].

The complete combustion of acetic acid ([tex]CH_3COOH[/tex]), the main active ingredient in vinegar, can be represented by a balanced chemical equation. In combustion reactions, a compound reacts with oxygen ([tex]O_2[/tex]) to produce carbon dioxide ([tex]CO_2[/tex]) and water ([tex]H_2O[/tex]).

Step 1: Write the unbalanced equation

[tex]\text{CH}_3\text{COOH} + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}[/tex]

Step 2: Balance the carbon atoms

Since acetic acid contains two carbon atoms, we require two [tex]CO_2[/tex] molecules:

[tex]\text{CH}_3\text{COOH} + \text{O}_2 \rightarrow 2 \text{CO}_2 + \text{H}_2\text{O}[/tex]

Step 3: Balance the hydrogen atoms

There are 4 hydrogen atoms in acetic acid, so we need 2 [tex]H_2O[/tex] molecules:

[tex]\text{CH}_3\text{COOH} + \text{O}_2 \rightarrow 2 \text{CO}_2 + 2 \text{H}_2\text{O}[/tex]

Step 4: Balance the oxygen atoms

On the right side, there are 4 oxygen atoms in 2 [tex]CO_2[/tex] and 2 oxygen atoms in 2 [tex]H_2O[/tex], totaling 6 oxygen atoms. On the reactant side, we have 2 oxygen atoms in 1 acetic acid molecule and need 4 more from [tex]O_2[/tex], so we need 2 [tex]O_2[/tex] molecules:

[tex]\text{CH}_3\text{COOH} + 2 \text{O}_2 \rightarrow 2 \text{CO}_2 + 2 \text{H}_2\text{O}[/tex]

The final balanced equation is:

[tex]\text{CH}_3\text{COOH} + 2 \text{O}_2 \rightarrow 2 \text{CO}_2 + 2 \text{H}_2\text{O}[/tex]

In atomic science, the z number refers to the number of __________ in the nucleus of an atom.

Answers

By convention, the symbol Z is assigned to the number of protons in the nucleus, or simply, the atomic number of an element. This is actually used when you want to determine the effective nuclear charge of a specific electron of an element. The equation is:

Z* = Z - S
where
Z* is the effective nuclear charge
Z is the atomic number
S is the number of electrons between the electron in question and the nucleus

There is due to a phenomenon called the shielding effect. This effect states that the farther the electron is from the nucleus, the lesser is its pull of force to the nucleus. That is the reason why the valence electrons (outermost electrons) are the ones always involved in chemicals reactions. Because they are not that strongly bonded to the nucleus of an atom.

When discussing acids and bases, any substance that donates a proton, by definition, is considered a(n)
a. arrhenius acid.
b. arrhenius base.
c. brønsted-lowry acid.
d. brønsted-lowry base?

Answers

Bronsted-Lowry acid is your answer

Which substance listed below is a polar molecule? all of the compounds nh41+ sicl4 cl2o none of the compounds?

Answers

Answer:

[tex]NH_4^+[/tex] and [tex]SiCl_4[/tex]

Explanation:

Hello,

In this case, in order to know whether a molecule is polar or not, the difference between the electronegativities of the bonding elements must be within the rank 0.7 and 1.6. In this manner, such difference is computed as follows for the given compounds:

- [tex]NH_4^+[/tex] --> [tex]\Delta E=3.0-2.1=0.9[/tex]

- [tex]SiCl_4[/tex] --> [tex]\Delta E=3.0-1.8=1.2[/tex]

- [tex]Cl_2O[/tex] --> [tex]\Delta E=3.5-3.0=0.5[/tex]

In such a way, both [tex]NH_4^+[/tex] and [tex]SiCl_4[/tex] are polar molecules unlike [tex]Cl_2O[/tex] which is apolar.

Best regards.

Final answer:

Among the provided options, Cl2O is the polar molecule due to an uneven distribution of electron charge resulting from the difference in electronegativity between Oxygen and Chlorine atoms.

Explanation:

In the given list, Cl2O (Dichlorine monoxide) is the polar molecule. A molecule is polar when it has an uneven distribution of electron charge resulting in regions of partially positive and partially negative charges. In Cl2O, oxygen is more electronegative than chlorine thus the shared electrons are more attracted towards the oxygen atom, creating a dipole, and thus making the molecule polar.

Additional Information

SiCl4 (Silicon tetrachloride) is a nonpolar molecule because the four Chlorine (Cl) atoms are evenly distributed around the Silicon (Si) atom, ensuring a balanced charge. As for NH4^+ (Ammonium), it is an ion, not a molecule, so it is not eligible for being polar or nonpolar.

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A solution that is 0.20 m in hcho2 and 0.15 m in nacho2 find ph

Answers

Final answer:

The pH of a buffer solution such as the one presented, made of a weak acid and its salt, is calculated using the Henderson-Hasselbalch equation. However, without the Ka value (acid dissociation constant) for the weak acid, the exact pH cannot be calculated.

Explanation:

This question is relating to the concept of buffer solutions in chemistry, particularly the pH calculation of a buffer solution made from a weak acid (HCHO2) and its salt (NaCHO2). The pH of a buffer solution is calculated using the Henderson-Hasselbalch equation, which is pH = pKa + log ([A-]/[HA]). That said, the exact pH cannot be calculated without the given Ka (acid dissociation constant) value for HCHO2. However, with the PH and Ka values, one would substitute the values in the equation to obtain the final pH of the solution.

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To find the pH of a solution containing 0.20 M HCHO₂ and 0.15 M NaCHO₂, use the Henderson-Hasselbalch equation. Given the pKa of 3.75 for formic acid, the pH is calculated to be approximately 3.63.

Calculating the pH of a Solution Containing HCHO₂ and NaCHO₂

To determine the pH of a solution that is 0.20 M in HCHO₂ and 0.15 M in NaCHO₂, we can use the Henderson-Hasselbalch equation:

pH = pKa + log ([A⁻]/[HA])

For formic acid (HCOOH, also denoted as HCHO₂), the pKa is approximately 3.75.

Step-by-Step Calculation:

Identify the concentration of the acid (HCHO₂) and its conjugate base (CHO₂⁻, provided by NaCHO₂).

Substitute the values into the Henderson-Hasselbalch equation:

Given: [HCHO₂] = 0.20 M, [NaCHO₂] = 0.15 M, pKa = 3.75

pH = 3.75 + log (0.15 / 0.20)

3. Calculate the log term:

log (0.15 / 0.20) = log (0.75) ≈ -0.125

4. Add the terms together:

pH = 3.75 - 0.125 = 3.625

Therefore, the pH of the solution is approximately 3.63.

What is the molecular weight of one mole of H2CO3? g/mole

Answers

The answer is 62.026 g/mole

Answer:

The answer to the question is 62.026.

If iron pyrite, fes2, is not removed from coal, oxygen from the air will combine with both the iron and the sulfur as coal burns. if a furnace burns an amount of coal containing 202.33 g of fes2, how much so2 (an air pollutant) is produced?

Answers

This is an example of combustion reaction, a substance is reacted with oxygen to form products. The balanced reaction for the burning of FeS2 is:

2 FeS2 + 5.5 O2 ---> 4 SO2 + Fe2O3

Therefore based on stoichiometric ratio of the reaction, for every 2 moles of FeS2, 4 moles of SO2 is produced.

First, lets calculate for the number of moles of FeS2 supplied: (molar mass of FeS2 = 119.965 g/mol)

n FeS2 = 202.33 g / (119.965 g/mol)

n FeS2 = 1.6866 mol


Calculate for the number of moles of SO2 produced using the ratio:

n SO2 = 1.6866 mol (4 / 2) = 3.373 mol SO2

Converting to mass: (molar mass SO2 = 64.066 g/mol)

m SO2 = 3.373 mol * 64.066 g/mol

m SO2 = 216.10 g         (ANSWER)

Final answer:

When 202.33 g of iron pyrite (FeS2) is burned, it reacts with oxygen to produce approximately 216.10 g of sulfur dioxide (SO2), which is a harmful air pollutant.

Explanation:

If iron pyrite (FeS2) is not removed from coal before burning, it can react with oxygen to form sulfur dioxide (SO2), which is a harmful air pollutant. To determine how much SO2 is produced from 202.33 g of FeS2 we can use stoichiometry. The balanced chemical equation for the reaction is:

4 FeS2 + 11 O2 → 2 Fe2O3 + 8 SO2

From the equation, we see that 4 moles of FeS2 produce 8 moles of SO2. First, we calculate the moles of FeS2 in 202.33 g.

Given that the molar mass of FeS2 is approximately 119.98 g/mol (55.845 g/mol for Fe and 32.065 g/mol for S, multiplied by 2 because there are two sulfurs), we perform the following calculation:

202.33 g FeS2 × (1 mol FeS2 / 119.98 g FeS2) = 1.686 moles FeS2

Applying the stoichiometry from the balanced chemical equation:

1.686 moles FeS2 × (8 moles SO2 / 4 moles FeS2) = 3.372 moles SO2

Finally, we convert moles of SO2 to grams using its molar mass (approximately 64.066 g/mol):

3.372 moles SO2 × 64.066 g/mol = 216.10 g SO2

So, 202.33 g of FeS2 would produce approximately 216.10 g of SO2 when burned.

A molecule in which the central atom has no lone pairs and forms four single bonds is said to have a ________ shape.

Answers

it should be tetrahedral. Good example is CH4

Answer: tetrahedral

Explanation:

Hybridization is calculated using the Lewis dot structures of all the compounds.

Formula used to calculate the number of atomic orbitals around central metal atom is:

Number of atomic orbitals around central metal atom = Number of bond pairs + Number of lone pairs

Bond pairs for a double bond and triple bond is taken as 1 only.

Given:  Number of bond pairs = 4

Number of lone pairs = 0

If Number of atomic orbitals around central metal atom are 4 , the hybridization is [tex]sp^3[/tex] and electron domain geometry is tetrahedral.

Which answer provides the correct name for the following hydrocarbon?

Moving left to right: A hydrocarbon chain made of a methyl group (CH subscript three) single bond methylene (CH subscript two) single bond methylene (CH subscript two) single bond CH subscript two single bond methyl group (CH subscript three) .

It looks like:  CH3 - CH2 - CH2 - CH2 - CH3

pentene
pentane
2-pentane
pentyne

Answers

1) Hydrocarbon: CH3 - CH2 - CH2 - CH2 - CH3

2) Only single bonds => alkane => sufix ane

3) no substitutions

4) 5 carbons = > prefix penta.

Therefore, the name is pentane.

Answer: Option (b) is the correct answer.

Explanation:

In the given molecule, there are five carbon atoms attached linearly to each other will single bonds only.

So, it is known that when a compound contains only carbon and hydrogen atoms attached  single bondedly to each other then this type of hydrocarbon is known as alkane.

Their general formula is [tex]C_{n}H_{2n+2}[/tex], where n is the number of carbon atoms present. Suffine "ane" is added to the name of alkane.

Thus, we can conclude that name of the given hydrocarbon is pentane.

Which element has a reddish color in a gas and liquid state?

Answers

Answer: bromine.

Bromine is described as a red or red - brown or reddish - brown element and you can find some pictures in textbooks or internet that reflect this color, both as a gas and as a liquid.

When mixed with some organic clear solvents it produces a beautifull red mixture.

What type of contamination occurs if a paint chip falls in soup?

Answers

The answer is chemical contamination.

The paint of the paint chip is a mixture with may chemicals that are not safe to health but hazardous, so you must inmediately think that a food contaminated with paint should be properly discarded.

Paint include voc (volatile organic solvents), chemical resins, pigments, oxides (dryers) which indeed are harmful if ingested.

Final answer:

The contamination that occurs from a paint chip falling in soup can be physical but may also lead to chemical contamination if the paint contains lead, which poses serious health risks.

Explanation:

If a paint chip falls into soup, the type of contamination that occurs is called physical contamination, which involves foreign objects entering foodstuffs. However, if the paint is lead-based, this can also lead to chemical contamination, as lead is a toxic substance.

When paint peels and cracks, it creates lead dust that can be hazardous if ingested. Given the risks associated with lead, it is considered a significant public health concern, particularly because lead exposure can cause serious health issues.

The ingestion of lead can be particularly dangerous for children and can lead to numerous health problems, including cognitive impairments.

A sample of dolomitic limestone containing only caco3 and mgco3 was analyzed.
a.when a 0.2800 gram sample of this limestone was decomposed by heating, 75.0 milliliters of co2 at 750 mmhg and 20 degrees celcius were evovled. how many grams of co2 were produced.
b.write the equations for the decomposition of both carbonates described above.
c.it was also determined that the initial sample contained 0.0488 gram of calcium. what percent of the limestone by mass was caco3?
d.how many grams of the magnesium- containing product were present in the sample in (a) after it had been heated?

Answers

A. how many grams of co2 were produced?
We use the ideal gas equation,
PV = nRT
where P = pressure in atm (750/760) 
           V = Volume  (75.0 mL) 
           n = moles
           T = temperature in Kelvin (20+273.15=293.15) 

Substitute the given values,
(750/760 atm) (0.075L)=(n) (0.0820 L-atm/mol K) (293.15 K) 
n=0.00308 mol CO2

0.00308 (44.01 g / mol) = 0.136 g CO2 

B. write the equations for the decomposition of both carbonates described above.
Thee decomposition reaction are as follows:
MgCO3 -> MgO + CO2 
CaCO3 -> CaO + CO2 

C. what percent of the limestone by mass was caco3?
Molar mass of CaCO3 = 100.11g/mol 
mole fraction  of Ca in CaCO3 = 40.1 / 100.11 = 0.401 
1 / 0.401 (0.0448 g Ca) = 0.112 g CaCO3 

%CaCO3 = 0.112 / 0.280 x 100 = 40%

100% - 40% CaCO3 = 60% MgCO3 

D. how many grams of the magnesium- containing product were present?
0.6 * 0.2800g sample = 0.168g MgCO3 

mole fraction MgO in MgCO3 = 40.3 / 84.31 = 0.477 
0.477 mol fraction (0.168g MgCO3) = 0.080 g MgO in heated sample
Final answer:

To find the amount of CO2 produced from the limestone sample, apply the ideal gas law to convert the given volume and conditions to moles and subsequently to grams. Decomposition equations for CaCO3 and MgCO3 are provided. The percentage of limestone as CaCO3 and the mass of magnesium-containing product after decomposition are calculated using the given sample data.

Explanation:Calculations and Concepts Based on Dolomitic Limestone Analysis

A sample of dolomitic limestone containing only CaCO3 and MgCO3 was analyzed. When a 0.2800-gram sample was decomposed by heating, certain measurements of CO2 were recorded. To calculate the grams of CO2 produced, we would convert the volume of CO2 gas given in milliliters to liters, use the ideal gas law PV = nRT to find the number of moles of CO2, and then convert those moles to grams using the molar mass of CO2.

The decomposition reactions for both carbonates would be as follows:


 CaCO3 → CaO + CO2
 MgCO3 → MgO + CO2

To find the percentage of the limestone that was CaCO3, the mass of calcium in CaCO3 is used in ratio with the total mass of the sample:

Percentage of CaCO3 = (mass of Ca in CaCO3 / total mass of the sample) * 100%

The mass of the magnesium-containing product (MgO) present in the sample after heating can be calculated if the mass of MgCO3 initially present is known, or by subtraction of the mass of CaCO3 decomposed and the CO2 evolved from the original sample mass.

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According to the transparency how is nitrogen returned to the atmosphere

Answers

According to transparency, nitrogen is returned to the atmosphere through a process called denitrification.

The process goes as follows:
Ammonification: This occurs when the decomposers break down the the wastes of the organisms and release the nitrogen that these organisms contained in the form of ammonia
Nitrification: This occurs when the ammonia is oxidized into nitrites which further oxidize into nitrates by the bacteria in the soil
Denitrification: This occurs when anaerobic bacteria break down these nitrates, thus, producing nitrogen into the atmosphere.

improvements in which area would help reduce the possibility of damage to the environment when using uranium as a fuel?

Answers

I think it would be better control of fusion reactions.

Answer:

Improvements in the area of uranium extraction would contribute to reducing the possibility of environmental damage by using uranium as fuel.

Explanation:

Having a uranium rod as a nuclear fuel generating energy in a fission reactor is not simple, it is a complex and costly process since the uranium ore is extracted, generating in its different stages negative environmental impacts through waste and shipments of radioactive material.

Improvements in uranium extraction would significantly reduce the environmental impact of this process, mainly in water.

Have a nice day!

What element is oxidized in the following reaction? Zn + CuSO4 yields ZnSO4 + Cu

Answers

To determine which element is being oxidized, this is one approach that can be used.

Note: oxidation numbers are very similar to ionic charges, or charges that form as metals and nonmetals, undergo chemical bonding.

1) To note down the oxidation numbers for all elements/atoms in the substances, and then observe that if it is increasing then it is being oxidized, if it is reducing then it would be being reduced.

Zn + CuSO4 -> ZnSO4 + Cu

O +2 -2 -> +2 -2 0

Ignore the -2 as these are spectator ions that do not undergo the change, and are not part of the main reaction occurring.

Here we can see that Zn goes from 0 to +2, thus it would be oxidized, while Cu goes from +2 to 0, thus is reduced.

An element is said to be oxidized when they chemically react with an oxygen atom. In the reaction between zinc and copper sulfate, the zinc element is said to be oxidized.

What is oxidation?

In a redox reaction the atoms and molecules losses and gains electron to change their oxidation state by completely transferring their electrons to another atom in the reaction mixture.

Oxidation is the process of redox where the atom losses its electron which can be said as an increase in its oxidation number by giving away its electron or by the addition of oxygen.

The balanced reaction is given as,

Zn + CuSO₄ → ZnSO₄ + Cu

Here, the oxidation number of zinc changes from 0 to +2, and of copper from +2 to 0. It can be inferred that zinc got oxidized, while copper got reduced.

Therefore, in the reaction zinc got oxidized.

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The number of moles of oxygen gas needed to react with 4.0 moles of mg is

Answers

For four moles of mg we need 2 moles of oxygen to react completely
Final answer:

For 4.0 moles of magnesium to react completely, 2.0 moles of oxygen gas are needed, as per the stoichiometry of the balanced chemical reaction between magnesium and oxygen.

Explanation:

The number of moles of oxygen gas needed to react with 4.0 moles of magnesium can be determined by using the balanced chemical reaction: 2Mg(s) + O₂(g) → 2MgO(s). This equation tells us that two moles of magnesium react with one mole of molecular oxygen to form magnesium oxide. Therefore, if you have 4.0 moles of magnesium, you will need 2.0 moles of oxygen gas to fully react with all the magnesium.

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A substance that decreases hand increases ph when it dissociates in water is called

Answers

A substance that decreases hand increases ph when it dissociates in water is called a base

A base is a substance containing (OH)- group (hydroxide group) in its formula. This means that when a base is dissociated in water, hydroxide group (OH)- will be released in the water which leads to the decrease in the concentration of the hydrogen and increases the pH.

On the other hand, an acid contains H+ in its formula. This means that when acid dissociates in water, hydrogen is releases, thus, increasing hydrogen concentration and decreasing pH value.


An aqueous solution contains 0.050 m of methylamine. the concentration of h+ in this solution is __________ m. kb for methylamine is 4.4 × 10-4.

Answers

Final answer:

The concentration of hydroxide ion in a solution of methylamine is approximately 9.07 x 10^-7 M.

Explanation:

The concentration of hydroxide ion in a solution of methylamine can be found by using the relation:

Kw = [H+][OH-]

Given that the Kb for methylamine is 4.4 x 10-4, we can calculate the concentration of hydroxide ion using the formula:

[OH-] = sqrt(Kw/Kb) = sqrt(1.0 x 10-14/4.4 x 10-4)

Substituting the values and solving, we find that the concentration of hydroxide ion in the solution is approximately 9.07 x 10-7 M.

Calculate the mass of two moles of kbr

Answers

The mass of one mole of KBr is the molar mass.

The molar mass is the sum of the atomic masses of each atom times the number of  moles of atoms in the formula

So, molar mass of KBr is atomic mass of K * 1 + atomic mass of Br * 1

Atomic mass of K = 39.1 g/mol

Atomic mass of Br = 79.9 g /mol

=> molar mass of KBr = 39.1 g/mol + 79.9 g/mol = 119 g/mol

=> mass ot two moles of KBr = 2 moles * 119 g/mol = 238 g

Answer: 238 g

Which product of the oxidation of ethanol causes many of the symptoms of the "morning-after hangover"?

Answers

ethanol → acetaldehyde → acetic acid

CH₃CH₂OH → CH₃COH → CH₃COOH

What is the coefficient for the oxygen molecule in the chemical equation below? 2hgo → 2hg + ? o2?

Answers

This question is purely balancing the chemical equation where the number of atoms in reactants is equal to the number of atoms in products.
For the mentioned equation:
In the reactants, we have 2 atoms of Hg and 2 atoms of oxygen.
In the products, we should have 2 atoms of Hg and 2 atoms of oxygen.
Since the oxygen molecule is composed of 2 oxygen atoms, therefore the coefficient should be equal to 1 for the equation to be balanced.

Isotopes of an element will always differ in .

Answers

Isotopes of an element will always differ in atomic mass. 

Sodium hydrogen carbonate is used as a deodorant. Express your answer as a chemical formula.?

Answers

First step is to get the symbols of each component in the mentioned compound:
Sodium has the symbol: Na
Hydrogen carbonate has the symbol: HCO3

Second step is to balance these components:
As both components are monotonic, the ratio for their combination is 1:1

Third step is to write the formula:
Sodium hydrogen carbonate : NaHCO3

Is an element that is soft and easy to cut cleanly with a knife likely to be a metal or a nonmetal?

Answers

The substance is likely to be a metal.

Metals consist of a lattice structure with layers on top of one another. Due to this, pure metals are very ductile and malleable due to the slipping of the layers over one another. The softness and clean cuts are not possible with non-metals because they usually have rigid and brittle structures. 

Final answer:

A soft element that can be cleanly cut with a knife is likely a metal due to metals being malleable and ductile, in contrast to the brittleness of nonmetals.

Explanation:

An element that is soft and can be easily cut with a knife is likely to be a metal. This observation is in line with the known properties of metals. Metals are known to be good conductors of electricity and heat, shiny, silvery, solid, and exhibit malleability which allows them to be hammered or pressed into thin sheets, and ductility which means they can be drawn out into thin wires.

On the other hand, nonmetals are usually brittle in their solid forms and do not have the malleability that metals possess. Based on these definitions and properties, the characteristics of being soft and easily cut suggest that the element in question exhibits metallic properties. Alkali metals, in particular, are known for their softness and can indeed be cut with a simple lab spatula.

"if the average global intake of vegetables is 2,300 calories per day, how many liters of water are needed to produce these vegetable calories"

Answers

2,300 liters of water will be needed to produce the vegetables. Research had shown that underground water has more water drawn from them for human use than the water that flow into them naturally. It was reported that 2.300 liters of water is needed to produce 2,300 calories of vegetable food; 1,569,500 liters of water are needed for yearly food production.

What does the atomic number of an element represent?

Answers

Hello!
Whenever you see an atomic number with an element, you know the number of protons in the nucleus of the atom, which determines the chemical of an element and its place on the periodic table.

For example, Hydrogen has only one proton, however, if you were to add say 78 more protons, you'd get gold!


Answer:

The atomic number represents or stands for the distinct identity of a chemical element. It is usually defined as the number or protons present in an atom of an element, which is also equal to the number of electrons.

Explanation:

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