The first step to solve this problem is to write the chemical equation involved:
[tex]4NH_3+5O_2\to4NO+6H_2O[/tex]Use the mole ratio of ammonia to nitrogen monoxide which is 4:4 or 1:1 to find the moles produced by the given amount of ammonia:
[tex]1.4molNH_3\cdot\frac{4molNO}{4molNH_3}=1.4molNO[/tex]It means that the answer is 1.4 moles of nitrogen oxide.
Given this equation: 3 MgCl2 + 2 Al → 3 Mg + 2 AlCl3, if 2.1 moles of magnesium chloride reacted how many moles of aluminum chloride are produced?
Let's see that 3 moles of magnesium chloride (MgCl2) produce 2 moles of aluminum chloride (AlCl3), we can do a rule of three to find the number of moles required of AlCl3 by 2.1 moles of MgCl2, like this:
[tex]\begin{gathered} \text{3 moles MgCl}_2\to2molesAlCl_3 \\ 2.1molesMgCl_2\to?molesAlCl_3 \end{gathered}[/tex]The calculation would be:
[tex]2.1molesMgCl_2\cdot\frac{2molesAlCl_3}{3molesMgCl_2}=1.4molesAlCl_3.[/tex]So, the answer is that 1.4 moles of aluminum chloride are produced by 2.1 moles of magnesium chloride.
Why CAF2 , the formula unit is one Ca+2 ion and 2 F- ion?
We have here calcium fluoride CaF2.
This is a binary compound. It is formed by a nonmetal and a metal.
The metal is Ca and the nonmetal is F.
It is an inorganic compound.
If we write the reaction:
CaF2 ===> Ca+2 + 2 F-1
Oxidation state of Ca = +2
Oxidation state of F = - 1
If we balance this reaction, we will also have to balance the net charge here.
On the left, we have a charge = 0
On the right, we have +2 for Ca ion and -1 for F ion. But if you add these values, the result would be +1, and this would be wrong because we must have a 0 charge on the right too.
To solve this, we need to multiply by 2 the F- ion, then we will have +2 from Ca and 2 x (-1) = -2 from F ion. The net charge will be 0, as the charge on the left side of the reaction.
If you take a look you need to have the same number of atoms on both sides of the reaction.
In a sample of calcium metals, how many electrons does an atom of calcium contribute to the sea of delocalized electrons?
ANSWER
Calcium atom has two electrons to contribute to the sea of delocalized electrons
EXPLANATION
Calcium belongs to group two metals with the atomic number of 20
The electronic configuration of calcium is written below as
[tex]\text{ }_{20}\text{Ca }\rightarrow\text{ 1s}^22s^22p^63s^23p^64s^2[/tex]In the above configuration, calcium has two electrons at its outermost shell. This means it valence electrons is 2
Therefore, calcium is readily to lose the two electrons two attain it octet configuration.
Hence, calcium atom has two electrons to contribute to the sea of delocalized electrons
What is the name of Al3+ ?AluminumAluminide ionAluminum ionAluminous ion
An atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons.
In this case, we can see that Aluminum's atom is losing three electrons as it has a +3 charge, so:
The name of Al3+ is aluminum ion.
A 0.700L sample of gas at STP is compressed to a volume of 0.200L and the temperature is increased to 30 degrees Celcius . What is the new pressure of the gas (in atm)?
Answer: the pressure of the gas after the compression is 3.88 atm
Explanation:
The question requires us to calculate the new pressure of a gas, given its initial volume at STP, new volume after compression and temperature after compression.
The following information was provided by the question:
Initial volume = V1 = 0.700 L
Final volume = V2 = 0.200 L
Final temperature = T2 = 30 °C = 303.15 K
To solve this problem, we can apply the equation for ideal gases (shown below) considering the conditions after the compression:
[tex]P\times V=n\times R\times T\rightarrow P_2=\frac{R\times n\times T_2}{V_2}[/tex]where R is the constant of gases (R = 0.082057 L.atm/K.mol), n is the number of moles of gas, T2 is the temperature after compression and V2 is the volume after compression.
Note that the number of moles of gas remains the same even after compression. Thus, we can calculate this number of moles considering the inital volume at STP, knowing that 1 mol of a gas at Standard Temperature and Pressure corresponds to 22.4 L of this gas:
22.4 L ------------------------- 1 mol
0.700 L ----------------------- x
Solving for x, we'll have:
[tex]x=\frac{(0.700L)\times(1mol)}{(22.4L)}=0.0312mol[/tex]Therefore, the number of moles before and after compression is 0.0312 mol.
Now that we have the values for n, T2 and V2, we can calculate the pressure after compression (P2):
[tex]\begin{gathered} \begin{equation*} P_2=\frac{R\times n\times T_2}{V_2} \end{equation*} \\ P_2=\frac{(0.082057L.atm/K.mol)\times(0.0312mol)\times(30+273.15)K}{(0.200L)}=3.88atm \end{gathered}[/tex]Therefore, the pressure of the gas after the compression is 3.88 atm.
What is the difference between a polymer and a plastic?
Rather than presenting a marked difference between plastics and polymers, it should be emphasized that polymers are a group of compounds that encompass large molecules formed by the union of covalent bonds. Within the polymers there are some subgroups, these subgroups are classified according to the properties that the polymer has and its origin. They can come from natural or synthetic sources.
Plastics are a subgroup of synthetic polymers that possess temperature-sensitive properties, that is, they deform at a certain temperature, so their molding is done with heat.
How to Develop a Bohr model for Mg+
ANSWER
EXPLANATION
Given that;
[tex]\text{ Mg}^+[/tex]The atomic number of magnesium is 12.
In a neutal atom, the atomic number is equal to the number of proton
Therefore, the number of proton is 12
The magnesium ion lose one electron and it has 11 electrons
Hence, the Bohr model of Mg+ is drawn below as
What correctly identifies the relationship between the type of bond formed and the electronegativity of the atoms?
Remember that electronegativity measures the type of bond formed. When the electronegativity is above 1.7 it represents an ionic bond when the electronegativity is between 0.4 and 1.7 consists of a polar covalent bond, and when the electronegativity is under by 0.4 the bond is a polar non-covalent, so the answer is A: if the electronegativity difference between two atoms is above 1.7, the bond is ionic.
From this set, which atom has the highest electronegativity? Oxygen, nitrogen, neon, or helium?
Answer
Oxygen.
Explanation
The trend of electronegativity in the periodic table is: electronegativity generally increases as you move from left to right across a period and decreases as you move down a group.
As a result, the most electronegative elements are found on the top right of the periodic table, while the least electronegative elements are found on the bottom left.
That is alkali metals have the lowest electronegativities, while halogens have the highest. Because most noble gases do not form compounds, they do not have electronegativities.
Therefore, from the given set of atoms, the atom that has the highest electronegativity is oxygen.
When sodium thiosulfate pentahydrate dissolves in water in a beaker, the beaker becomes cold. Why?A.) This solute was cold when it was placed into the water.B.) Dissolving this solute is an exothermic process.C.) Dissolving this solute reaches a cold equilibrium point.D.) Dissolving this solute is an endothermic process.
When we make a mixture, the molecules and bonds present in each of the substances can exert attraction or repulsion and can absorb or release energy. This energy is evidenced by an increase or decrease in temperature.
When the mixture releases energy, the temperature will increase and is called exothermic. When the mixture absorbs energy, the temperature will decrease and is called endothermic.
Therefore, if the beaker becomes cold it means that the mixture of these two compounds is endothermic.
Answer: D.) Dissolving this solute is an endothermic process.
O
Name,
Period
Chapter 6 Practice
Choose the best answer:
1. Which of the following states the results of a sodium atom transferring an electron to a chlorine
atom.
a.
b.
Each atom ends up with a more stable electron arrangement.
The sodium atom becomes more stable, but the chlorine atom becomes less stable.
c. The chlorine atom becomes less stable, but the sodium atom becomes more stable.
d. Each atom ends up with a less stable electron arrangement.
To achieve stability Na⁺ looses its electron to chlorine ion to complete its octet, and cl⁻ gain electron from sodium ion to complete its octet, so option A and B both are right.
What is electronic configuration ?
According to electronic configurations, each electron moves individually within an orbital while being surrounded by an average field produced by all other orbitals.
The octet rule can be better understood by considering the electron configurations of sodium and chloride ions, which are the main ingredients of table salt ( NaCl ).
The Na+ ion has an electron configuration of 1s₂, 2s₂ ,2p₆ after sodium ( Na ), with an electron configuration of 1s₂, 2s₂, 2p₆, 3s₁, loses its outermost 3s electron.
So, chlorine atom gain one electron from sodium atom to complet octet and become stable.
Hence, option A and B both are correct.
To learn more about electronic configuration follow the link below;
https://brainly.com/question/28045031
#SPJ2
What is the molar mass of an unknown gas with a density of 2.65 g/L at 3.00 atm and 45.0 °C?
In order to solve this question, we will need to use two very common formulas, the first it will be the Ideal gas Law, but with a few changes, and the second it will be the density formula:
PV = nRT, this is the Ideal gas formula, and we have:
P = 3.00 atm
T = 45°C, but we need it in Kelvin, 318 K
R = 0.082, this is the gas constant
d = m/V, this is the density formula, and we have:
d = 2.65 g/L
Now let's make a few changes on the ideal gas formula, first switching n (number of moles) for m/MM (mass/molar mass)
PV = m/MM * RT
P*MM/RT = m/V, now we have m/V, which is the same as density, now we can use the values
3 * MM/0.082 * 318 = 2.65
3 * MM/26.076 = 2.65
3MM = 69.10
MM = 23.03g/mol, this is the final molar mass
Calculate the pH if [H+] = 3.95 x 10^-5 M
Answer
pH = 4.40
Explanation
Given:
[H⁺] = 3.95 x 10⁻⁵ M
What to find:
The pH of the solution.
Step-by-step solution:
Using the pH formula;
[tex]pH=-log[H^+][/tex]So,
[tex]\begin{gathered} pH=-log(3.95\times10^{-5}) \\ \\ pH=-(-4.40) \\ \\ pH=4.40 \end{gathered}[/tex]CaO(s)+ H2O(I) > Ca(OH)2(s)+ 65.2 KJ endothermic or exothermic
An endothermic reaction is a type of reaction in which we need an input of energy in order for the reaction to properly occur, we will usually see this type of reaction represented by the positive sign, whereas exothermic reactions are the opposite, they release energy as product of the reaction. In this question, since the sign of the energy is positive, we have an Endothermic reaction
Gatorade could be classified as which of the following?Question 4 options:compoundsolution (homogenous)mechanical mixture (heterogenous)element
A compound is just when 2 or more elements bond together and form sometimes a molecule or an ionic compound (NaCl and C6H12O6 for example), although the Gatorade drink has lots of compounds in it, is not a classification that fits it.
A homogenous solution is usually a liquid in which we don't see different phases, like water and oil for example, so in Gatorades case we see a homogenous solution because all of the salts and sugar are dissolved in water.
Mechanical mixture is more used in solids, and it doesn't have only one phase, but several, like chocolate chips, granola.
Element is what we find in the periodic table, and although Gatorade has lots of it, it is not the right classification, the same way as a compound classification.
What is the smallest particle in the list below?A piece of dustA cell of E. coliAn atomA skin cell
ANSWER
The smallest particle is an atom
EXPLANATION
An atom is defined as the smallest indivisible particle of a substance that can take part in a chemical reaction and still retain it properties
An atom make up everything in the universe
Hence, the smallest particle is an atom
Calculate the molarity of the following solution. (0.34 mol of LiNO3 in 6.42 L of solution)
Step 1
Molarity can be defined as follows:
[tex]Molarity\text{ \lparen M or mol/L\rparen = }\frac{Number\text{ of moles of LiNO3}}{Volume\text{ of solution \lparen L\rparen}}[/tex]---------------------------
Step 2
Information provided:
0.34 moles LiNO3
Volume = 6.42 L
---------------------------
Step 3
Procedure:
From step1,
Molarity = 0.34 moles/6.42 L
Molarity = 0.053 M
Answer: Molarity = 0.053 M
What is the molarity of a solution that has 78 grams of H2SO4, (98.0 g/mol) dissolved in 1.75 liters ofsolution?
Answer
Molarity (C) = 0.455 mol/L
Explanation
Given:
Mass of H2SO4 = 78 g
Molar mass of H2SO4 = 98.0 g/mol
Volume of the solution = 1.75 L
Required: The molarity of the solution
Solution
Step 1: Calculate the number of moles of moles of H2SO4
n = m/M where n is the moles, m is the mass and M is the molar mass
n = 78 g/98.0 g/mol
n = 0.796 mol
Step 2: Calculate the molarity of the solution
C = n/V where C is the molarity/concentration, and V is the volume of the solution
C = 0.796 mol/1.75 L
C = 0.455 mol/L
eredA compound that contains only carbon, hydrogen,and selenium is 84.9 % Se and 12.9 % C by mass.Mass spectrometry data indicate the molar mass ofthis compound is 372 g/mol. What is the molecularformula of this substance?How to enter your answer: Suppose you deduce aformula of C6H7Se5. Enter it as C6H7Se5
Answer:
[tex]C_4H_8Se_4[/tex]Explanation:
Here, we want to get the molecular formula of the substance
We start by dividing the percentages by the atomic masses of the individual elements
The atomic mass of Selenium is 79 amu
The atomic mass of Carbon is 12 amu
The atomic mass of hydrogen is 1 amu
From the given percentages, to get the percentage for hydrogen, we subtract the percentages of carbon and selenium
We have that as 100- (12.9 + 84.9) = 2.2%
We have the calculation as follows:
[tex]\begin{gathered} Selenium \\ \frac{84.9}{79}\text{ = 1.075} \\ \\ Carbon \\ \frac{12.9}{12}=\text{ 1.075} \\ \\ Hydrogen \\ \frac{2.2}{1}\text{ = 2.2} \end{gathered}[/tex]From the above, we can see that the minimum value is 1.075
Now, we divide the values by the smallest
We have that as:
[tex]\begin{gathered} Selenium \\ \frac{1.075}{1.075}\text{ = 1} \\ Carbon \\ \frac{1.075}{1.075}\text{ = 1} \\ Hydrogen \\ \frac{2.2}{1.075}\text{ = 2} \end{gathered}[/tex]We can see that the empirical formula is thus:
[tex]CH_2Se[/tex]Now, let us get the molecular formula
We have to find the mass of the empirical formula, then divide the molar mass by it
This will give us the required multiple needed to get the molecular formula from the empirical formula
Mathematically, we have that as:
[tex]\begin{gathered} (79\text{ + 2\lparen1\rparen + 12\rparen n = 372} \\ 93\text{ = 372} \\ n\text{ = }\frac{372}{93}\text{ = 4 } \end{gathered}[/tex]This means that the molecular formula is:
[tex]C_4H_8Se_4[/tex]Select the correct answer.The image shows the combustion of methane. Which equation represents this chemical reaction?+–A.CH4 + 0₂ - CO₂ + H₂OB.2CH4 +20₂ - CO₂ + 2H₂OOC. CH4 +20₂ - 2CO₂ + H₂OD.CH4 + 0₂ - 2CO₂ + 2H₂OE.CH4 +20₂ - CO₂ + 2H₂O
Answer
E
Explanation
The combustion of CH4 is when CH4 reacts with oxygen to produce carbon dioxide and water in the following balanced equation:
[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]All the other e
Convert 7.07 mg to kgDo not use scientific notationInclude three significant figuresInclude the final unit
Answer:
[tex]\text{ 0.00000707 kg}[/tex]Explanation:
Here, we want to convert from mg to kg
Mathematically:
[tex]\begin{gathered} 1kg=10^6\text{ mg} \\ 1mg=10^{-6}\operatorname{kg} \end{gathered}[/tex]To convert the given value to kg, we have to divide it by 10 raised to the power of -6
Thus, we have it that:
[tex]\frac{7.07}{10^{-6}}\text{ = 0.00000707 kg}[/tex]What is it called when a solid changes directly into a gas? From a solid into a liquid?
ANSWER
The process of a solid changing to a gas is called SUBLIMATION
The process of solid turning to liquid is called MELTING
EXPLANATION:
Sublimation is the transition of a substance directly from the solid phase to the gas phase without passing through the liquid phase.
This occurs when the particle of the solid acquires enough energy to completely overcome the force of attraction holding the solid particles together.
Example: dry ice in water changing directly to carbon dioxide gas
Therefore, the process of a solid changing to a gas is called SUBLIMATION
The process of solid turning to liquid is called MELTING
What volume of carbon dioxide is produced when 25.3g propane (C3H8) is burned completely?
38.55L
Explanations:
Given the following parameters
Mass of propane = 25.3 grams
Determine the moles of propane
Moles of propane = Mass/molar mass
Moles of propane = 25.3/44.1
Moles of propane = 0.574moles
The combustion of propane is given according to the equation below:
[tex]C_3H_8+5O_2\rightarrow3CO_2+4H_2O[/tex]According to stoichiometry, 1mole of propane produces 3 moles of CO2, the moles of CO2 required will be:
[tex]\begin{gathered} mole\text{ of CO}_2=3\times0.574 \\ moles\text{ of CO}_2=1.721moles \end{gathered}[/tex]Since 1 mole = 22.4L, volume of CO2 gas that will be produced is:
[tex]\begin{gathered} volume\text{ of CO}_2=1.721\times22.4 \\ volume\text{ of CO}_2=38.55L \end{gathered}[/tex]Hence the volume of carbon dioxide produced is 38.55L
Match the term to its definition.NonpolarDiatomicPolarElectronegativityIonic?Composed of two atoms?A bond with a negative end and a positive end?A bond with equal sharing of electrons?A bond formed between ions
Answer:
Nonpolar = A bond with equal sharing of electrons.
Diatomic = Composed of two atoms.
Polar = A bond with a negative end and a positive end.
Electronegativity = the ability of an atom to attract electrons.
Ionic = A bond formed between ions.
Explanation:
Let's review each concept:
Nonpolar: a nonpolar covalent bond is a covalent bond in which the bonding electrons are shared equally between the two atoms.
Diatomic: it is a molecule that contains two atoms of the same or different elements.
Polar: a polar covalent bond is a covalent bond in which the atoms have an unequal attraction for electrons, and so the sharing is unequal.
Electronegativity: it is the tendency of an atom to form covalent or ionic bonds.
Ionic: an ionic compound is a compound that contains positive and negative ions.
Based on the last concepts, we have the answers are:
Nonpolar = A bond with equal sharing of electrons.
Diatomic = Composed of two atoms.
Polar = A bond with a negative end and a positive end.
Electronegativity = the ability of an atom to attract electrons.
Ionic = A bond formed between ions.
what is the relationship between the proton number and atomic number of an atom?
1) Proton. A proton is a positive particle found in the nucleus. The number of these particles defined the properties of an element.
We refer to the proton number as the atomic number. So, the proton number and the atomic number are the same.
True or false; A change in temperature will disturb the equilibrium state of a reaction by causing a shift to the left or to the right.
A change in temperature will affect the equilibrium state of a reaction. For example,
The position of equilibrium will move to the right if we increase temperature. More A and B are converted into C and D at the lower temperature. Increasing the temperature of a system in dynamic equilibrium favours the endothermic reaction.
Therefore the statement is true.
3.135 g of Ice is placed in a beaker of water. The water temperature in the beaker is 67 °C. After all the icemelts, the final water temperature in the beaker is 19.7 °C. 4 ptsHeat of fusion for water - 334 J/g. Specific heat of water 4.184 J/g °C. T2-T1 - 47.3°C.Note there are a couple different ways to solve this problem() Determine the initial volume of water in the beaker (before the ice was added),(b) Determine the final volume of water in the beaker (after all the ice has melted),.
Explanation:
We have 135 g of ice and we place it inside a beaker with hot water. The final temperature of the mixture is 19.7 °C, so the ice will cool the hot water.
The ice will melt and its temperature will increase from 0°C to 19.7 °C (if we suppose that the initial temperature of ice is 0°C).
First we have to determine the amount of energy that the ice absorbed to melt.
ΔHf = Cf * m
Where ΔHf is the amount of energy that the ice will absorb, Cf is the heat of fusion and m is the mass of ice in this case.
Cf = 334 J/g m = 135 g
ΔHf = Cf * m
ΔHf = 334 J/g * 135 g
ΔHf = 45090 J
Once the ice is melted, that sample of water will increase its temperature from 0 °C to 19.7 °C. Let's find the amount of heat that it is necessary to do that.
Q = m * C * ΔT
Where Q is the amount of heat that the water will absorb, C is the specific heta of water and ΔT is the change in temperature.
Q₁ = m * C * ΔT
Q₁ = 135 g * 4.184 J/(g°C) * (19.7 °C - 0.0 °C)
Q₁ = 11127 J
The total amount of energy that the ice will absorb to go from solid ice at 0°C to liquid water at 19.7 °C is:
Qice = Q₁ + ΔHf
Qice = 11127 J + 45090 J
Qice = 56217 J
The ice is absorbing energy from the hot water that was in the beaker. So the heat that the ice gained is the same amount of heat that the hot water released with opposite sign.
Qice = - Qhw
Qhw = -56217 J
The heat that the hot water gave to the ice can be calculated using this formula.
Qhw = m * C * ΔT
We can replace the values that we already know and solve that equation for m to get the initial volume of water in the beaker.
Qhw = m * C * ΔT
- 56217 J = m * 4.184 J/(g *°C) * (19.7 °C - 67.0 °C)
m = -56217 J /(4.184 J/(g*°C) * (-47.3 °C)
m = 284 g
Since the density of water is 1 g/mL, we can convert the mass of water into volume.
Initial volume = 284 g / (1 g/mL)
Initial volume = 284 mL
Now we know the volume of water that was in the beaker before the ice is added, and we are given the mass of ice. We can find the final volume of water in the baker.
Final volume = initial volume + volume from ice
Final volume = 284 mL + 135 g /(1 g/mL)
Final volume = 419 mL
Answer:
a) The initial volume of water in the beaker was 284 mL.
b) The final volume of water in the beaker is 419 mL.
which of the first long is true for water molecule
Answer:
[tex]D[/tex]Explanation:
Here, we want to select the correct option for a water molecule
In a water molecule, the atoms present are 2 hydrogen atoms and 1 oxygen atom
While the hydrogen is positive, the oxygen is negative
Thus, from the list of options given, the oxygen atom is slightly negative in charge is the correct option
In the space below, draw the electron dot diagram for the atom shown above. Then explainwhat the letter and the dots in the diagram mean. Name another element that would havethe same number and arrangements of valence electrons.
Answer:
-The letter O is the symbol of the element while the dots represent the electrons
- Another element with the same arrangement of valence electrons would be Sulfur (they belong to the same group)
Explanation:
Here, we want to draw the electron dot diagram for the atom
The electron dot diagram will only recognize the valence electrons which are the electrons that help it in partaking in chemical reactions
From the image shown, the atom has 6 valence electrons (in the outermost shell)
Thus, we have the dot diagram as follows: Let us call the atom X:
The letter O is used to represent the symbol of the element which is Oxygen in the real sense.
The letters 16 p and 16 n represent 16 neutrons and 16 protons respectively. The very black circle represents the nucleus where the neutrons and protons reside
Since the valence electrons contain 6 electrons, another element with a similar arrangement of valence electrons would be an element in the same group which in this case is sulfur
Which of the following happens during a chemical change but does not happen during a physical change? (1 pO The mass of the substance changes.O Atoms of one or more substances rearrange into a new substance.O The state of the substance changes.O The appearance of a substance changes, but it is still the same substance.
Answer:
Atoms of one or more substances rearrange into a new substance. (second )
Explanation:
When a chemical change occurs, the original substance before the change is different from the substance after the change, in this case, that change is due to the fact that the atoms of one or more substances are rearranged into a new substance, since the other options include a physical change.