Answers
Answer:
i think correct
Explanation:
i am not sure but i hope it will help you
Related Questions
I need some help with chem, how do you know whether the reaction is endothermic or exothermic? Pls provide examples.
Thank you!!
Answers
Answer:
Basing on explanations below;
1. Endothermic reactions have a positive enthalpy while Exothermic reactions have a negative enthalpy.
2. Endothermic reactions take place in high temperatures while Exothermic reactions take place in low temperatures.
When sulfuric acid is added to solid sodium chloride and the mixture is heated, hydrogen chloride gas is generated, leaving a residue of sodium sulfate
Answers
The balanced chemical equation for the reaction between sulfuric acid and sodium chloride to produce hydrogen chloride gas and sodium sulfate is:
2H₂SO₄ + 2NaCl -> 2HCl + Na₂SO₄
What is the equation about?The equation given above is:
Sulfuric acid + sodium chloride -> hydrogen chloride + sodium sulfate
Therefore, In this equation, sulfuric acid (H₂SO₄) is the acid and sodium chloride (NaCl) is the base. The acid donates protons (H+ ions) to the base, resulting in the production of hydrogen chloride gas (HCl) and a salt (Na₂SO₄).
The overall reaction is an example of an acid-base reaction, in which the acid and base react to produce a salt and a neutralization product (in this case, HCl).
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See full question below
When sulfuric acid is added to solid sodium chloride and the mixture is heated, hydrogen chloride gas is generated, leaving a solid residue of sodium sulfate. Give the balanced chemical equation for this reaction.
What can cause a mutation when the cell copies its DNA?
All of the above
Exposure to chemicals
Exposure to radiation
Errors
Answers
Answer:
exposure to radiation i think
Explanation:
do covalently bonded atoms also form ions?
Answers
Yes, covalently bonded atoms can also form ions.
Ions are atoms or molecules that have an electric charge due to an unequal number of protons and electrons. This can occur in covalently bonded atoms when one atom has a greater affinity for electrons than the other, resulting in the transfer of one or more electrons from one atom to the other.
For example, in a covalent bond between hydrogen and oxygen, hydrogen has a greater affinity for electrons than oxygen, so it can pull an electron away from oxygen and form an ionic bond. The oxygen atom now has a negative charge, becoming an anion, while the hydrogen atom has a positive charge, becoming a cation.
In summary, covalently bonded atoms can also form ions due to an unequal electron affinity between the two atoms. This creates an ionic bond, where one atom has a negative charge (anion) and the other has a positive charge (cation).
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When the wax is heated to a liquid state, the paint can be spread.
(a) True
(b) False
Answers
The statement that when wax is heated to a liquid state, the paint can be spread is true
When wax is heated, it undergoes a phase transition from its solid state to a liquid state. As the temperature increases, the intermolecular forces holding the wax molecules together weaken, allowing them to move more freely.
In the solid state, wax typically has a rigid and solid structure with limited mobility of its molecules. However, when heat is applied, the wax molecules gain thermal energy, causing them to vibrate and overcome the forces that hold them in place. As a result, the wax transitions into a liquid state.
In the liquid state, the wax molecules are now able to flow and move past each other more easily. This increased mobility and decreased viscosity of the liquid wax make it suitable for spreading. When the liquid wax is applied to a surface, such as for painting, it can be spread smoothly and evenly due to its fluid nature.
The ability of wax to be spread when heated is utilized in various applications, including candle making, wax sealing, and encaustic painting. In these processes, the wax is melted to a liquid state, allowing it to be manipulated and applied as desired.
Therefore, the statement that when wax is heated to a liquid state, the paint can be spread is true.
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Consider the following species when answering the following questions:
(i) PCl3 (ii) CCl4 (iii) TeCl4 (iv) XeF4 (v) SF6
For which of the molecules is the molecular geometry (shape) the same as the VSEPR electron domain arrangement (electron domain geometry)?
Answers
The molecular geometry (form) of CCl4 SF6 is identical to the configuration of the electron domains in a VSEPR.
Is VSEPR and molecular geometry equivalent?VSEPR distinguishes between molecular geometry, which defines how the atoms in a molecule are ordered, and electron group geometry, which expresses how electron groups (bonds and nonbonding electron pairs) are arranged.
What do electron domains and molecule structure reveal from VSEPR?Chemistry frequently employs the valence-shell electron-pair repulsion (VSEPR) model to foretell the three-dimensional organization, or geometry, of molecules. This model accounts for the repulsion between electron pair to estimate the structure of a molecule.
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How much heat is roguired to raise the temperature of 8.75 g of water from its melting point to its boiling pointsExpress your answer numerically in kilojoulos,
Answers
The heat required to raise the temperature of 8.75 g of water from its melting point to its boiling points is 3.662 kJ.
What exactly is specific heat?The amount of heat required to increase the temperature of one gram of a material by one degree Celsius (°C) is defined as specific heat.
What is the name of the specific heat formula?The equation q = mcΔt can be used to compute the amount of heat acquired or lost by a specific heat (q), where m is the mass of the sample, c is the specific heat, and Δt is the temperature change.
Given:
m = 8.75
c = 4.186 J/g°C
The melting point and boiling point of water is 0° and 100° respectively.
Δt = 100° - 0° = 100°
We know that,
q = mcΔt
= 8.75(4.186)100
= 3.662 kJ
Thus, the heat required to raise the temperature of 8.75 g of water from its melting point to its boiling points is 3.662 kJ.
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which of the following statements correctly describe the angular momentum quantum number, symbol l?
Answers
The correct answer is:
e. All of the above are true.
Explanation:
a. The angular momentum quantum number (l) describes the size and energy associated with an orbital. It determines the shape of the orbital.
b. The magnetic quantum number (ml) describes the orientation of the orbital. It specifies the spatial orientation of the orbital within a subshell.
c. An orbital is the path that an electron follows during its movement in an atom. This statement is true.
d. The principal quantum number (n) describes the energy level or shell of an orbital. It determines the overall size and average distance of the electron from the nucleus.
All of these statements are true and correctly describe different aspects of quantum numbers and orbitals in an atom.
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--The question is incomplete , the complete question is given below:
"Which of the following statements is true? a. The angular momentum quantum number (l) describes...
a. The angular momentum quantum number (l) describes the size and energy associated with an orbital.
b. The magnetic quantum number (ml) describes the orientation of the orbital.
c. An orbital is the path that an electron follows during its movement in an atom.
d. The principal quantum number (n) describes the shape of an orbital.
e. All of the above are true."--
Which of the following is a hydrocarbon? (Concept 4.2)
A) C6H12O6
B) H2CO3
C) CO2
D) CCl2F2
E) C3H8
Answers
Of the following compounds given E) \(C_3H_8\) is the only hydrocarbon.
\(C_3H_8\) is a hydrocarbon. It is a chemical formula representing propane, which is a saturated hydrocarbon belonging to the alkane family. Hydrocarbons are organic compounds composed solely of hydrogen and carbon atoms. They can exist as gases, liquids, or solids and are an essential component of fossil fuels and many other organic compounds.
Option A (\(C_6H_12O_6\)) represents glucose, a carbohydrate, which contains oxygen in addition to carbon and hydrogen atoms. Option B (\(H_2CO_3\)) represents carbonic acid, which is an inorganic compound containing carbon, hydrogen, and oxygen atoms. Option C (\(CO_2\)) represents carbon dioxide, an inorganic compound composed of carbon and oxygen atoms. Option D (\(CCl_2F_2\)) represents dichlorodifluoromethane, which is a chlorofluorocarbon (CFC) and not a hydrocarbon.
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why is edta used to determine the hardness of water
Answers
EDTA (ethylenediaminetetraacetic acid) is commonly used to determine the hardness of water due to its ability to form complexes with metal ions, particularly calcium and magnesium ions.
Water hardness refers to the concentration of calcium and magnesium ions present in water. These ions can cause scaling, reduce the effectiveness of soaps, and have other negative effects. EDTA acts as a chelating agent, meaning it can bind to metal ions and form stable complexes.
In the process of determining water hardness, a known amount of EDTA solution is added to a water sample. The EDTA molecules form complexes with the calcium and magnesium ions present in the water.
The endpoint of the titration is reached when all the metal ions are complexed by the EDTA, resulting in a color change or an indicator reaching a specific endpoint.
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someone help me plz :))) brainliest
Answers
Answer:
Option 2
Explanation:
Which of an atom's electrons are involved in chemical reactions?
a. The electrons farthest from the nucleus of the atom
b. The electrons that make one isotope different from another
c. The electrons that determine the atomic number of the atom
d. The electrons closest to the nucleus of the atom
Answers
Answer:
A is the correct answer
Answer:
A. The electrons farthest from the nucleus of the atom
Explanation:
1) How many molecules of K2CrO4 are in 0.6 moles?
2) How many atoms of K are in 0.6 moles of K2CrO4?
3) You dilute 0.5 mol of NaOH to form 2 L of solution. What is the Molarity of that solution?
4) You dissolve 50 g of sugar to make 250 g of sugar water. What is the percent by mass?
5) A 2 L bottle of 5% vinegar has how much vinegar by volume?
Answers
Given the various data from the question, the answers to each question is given below:
1. How to determine the number of moleculesAvogadro's hypothesis
1 mole of K₂CrO₄ = 6.02×10²³ molecules
Therefore,
0.6 mole of K₂CrO₄ = 0.6 × 6.02×10²³
0.6 mole of K₂CrO₄ = 3.612×10²³ molecules
2. How to determine the number of atoms1 mole of K₂CrO₄ contains 2 moles of K.
Therefore,
0.6 mole of K₂CrO₄ will contain = 0.6 × 2 = 1.2 mole of K
From Avogadro's hypothesis,
1 mole of K = 6.02×10²³ atoms
Therefore,
1.2 mole of K = 1.2 × 6.02×10²³
1.2 mole of K = 7.224×10²³ atoms
Therefore, we can say that
0.6 mole of K₂CrO₄ = 7.224×10²³ atoms of K
3. How to determine the molarityMolarity is defined as:
Molarity = mole / Volume
From the question given above, we obtained the following:
Mole = 0.5 mole Volume = 2 LMolarity =?Molarity = mole / Volume
Molarity = 0.5 / 2
Molarity = 0.25 M
4. How to determine the volumeFrom the question given above, the following data were obtained:
Mass of solute = 50 gMass of solution = 250 gPercentage of sugar =?Percentage = (mass of solute / mass of solution) × 100
Percentage of sugar = (50 / 250) × 100
Percentage of sugar = 20%
5. How to determine the volumeTotal volume = 2 L
Percentage of vinegar = 5%
Volume of vinegar =?
Volume = percent × total volume
Volume of vinegar = 5% × 2
Volume of vinegar = 0.1 L
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What is the ionic equation for this reaction:
MgO (s) + 2HCl (aq) = MgCl2 (aq) + H2O (l)
Please let me know how you worked it out, thankyou!!
Answers
Answer:
\(MgO _{(s)} + 2H {}^{ + } _{(aq)} = Mg {}^{2 + } _{(aq)}+ H _{2} O _{(l)} \\ \)
If the reaction began with 0.100m of N2, O2, and NO. What is the equilibrium concentration (in m) of NO report?
Answers
The equilibrium concentration of NO is 0.044 M.
The given reaction is : N2(g) + O2(g) ⇌ 2NO(g)
Initially, the concentrations are as follows : [N2] = [O2] = [NO] = 0.100 M.
Let us suppose that the equilibrium concentration of NO is x M.So, at equilibrium, the concentrations of N2 and O2 will become (0.100 - x) M because 2 moles of NO are formed by reacting 1 mole each of N2 and O2.
Therefore, the equilibrium constant expression becomes as follows :
Kc = [NO]²/([N2] [O2])Kc = (x)² / (0.100 - x)²
Since Kc is 2.4 x 10⁻³ M, substitute all the values : 2.4 x 10⁻³ = x² / (0.100 - x)²
Solve for x using algebra : (0.100 - x)² = x² / 2.4 x 10⁻³0.100² - 0.200x + x²
= x² / 2.4 x 10⁻³0.100² - 0.200x = x² / 2.4 x 10⁻³x³ - 0.0072x² - 0.200x + 0.001 = 0
This cubic equation can be solved by using a graphical calculator or a software to get the value of x, which is 0.044 M (approx).
Therefore, the equilibrium concentration = 0.044 M.
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What is a unit cell? Provide simple definition. (b) Sketch the body-centered cubic unit cell. (c) For the BCC unit cell, define the coordination number using a sketch. (d) Show the calculation (with all terms defined) for determining the atomic packing factor (APF) for the BCC unit cell (assume hard ball, spherical atoms).
Answers
A unit cell can be visualized as a building block that, when replicated in all directions, creates the entire crystal lattice. Unit cells can have different shapes, the most common types of unit cells include simple cubic, body-centered cubic, and face-centered cubic etc.
(a) Definition of a unit cell: A unit cell is the basic repeating unit of a crystal lattice. It represents the smallest portion of a crystal that, when stacked together, can generate the entire crystal structure.
(b) Sketch of a body-centered cubic (BCC) unit cell is represented in the image below. In the BCC unit cell, atoms are located at the eight corners of the cube and one atom is positioned at the center of the cube.
(c) Coordination number in a BCC unit cell: The coordination number is the number of nearest neighboring atoms surrounding a central atom. In a BCC unit cell, each atom is in contact with eight nearest neighboring atoms: one in the center of the unit cell and one at each of the eight corners.
(d) Calculation for the atomic packing factor (APF) of a BCC unit cell:
The APF is calculated as the volume occupied by the atoms in the unit cell divided by the total volume of the unit cell.
For a BCC unit cell, the APF can be calculated as follows:
APF = (Number of atoms in the unit cell * Volume of each atom) / Volume of the unit cell
In a BCC unit cell, there are two atoms (one at the center and one at the corner), and the volume of each atom can be approximated as (\(4/3\)) * π * \((radius)^3\). The volume of the unit cell can be calculated as the cube of the edge length.
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1.50 × 1024 molecules of oxygen are burned in a combustion reaction. What is the mass of O2 consumed in the reaction?
Answers
If 1.50 × 1024 molecules of oxygen are burned in a combustion reaction. The mass of O2 consumed in the reaction is 80.0 g.
How to find the mass of 02?The balanced chemical equation for the combustion of oxygen (O2) is:
2 O2 + energy → 2 O
This equation tells us that for every 2 molecules of O2 that are burned, 2 molecules of O are produced.
We are given the number of molecules of O2, which is 1.50 × 10^24. To determine the mass of O2 consumed in the reaction, we need to use the molar mass of O2 and stoichiometry.
The molar mass of O2 is 32.00 g/mol (2 × 16.00 g/mol). We can use this molar mass to convert the number of molecules of O2 to its mass:
1.50 × 10^24 molecules O2 × (1 mol O2 / 6.022 × 10^23 molecules O2) × (32.00 g O2 / 1 mol O2) = 80.0 g O2
Therefore, the mass of O2 consumed in the reaction is 80.0 g.
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what is the pressure (in atmospheres) of the gas inside the container connected to an open-end, mercury-filled manometer as shown in the picture? (figure 1) the atmospheric pressure is 0.95 atm .
Answers
The pressure (in atmospheres) of the gas inside the container connected to an open-end, mercury-filled manometer is 1.19 atm
How do I determine the pressure of the gas?The pressure of a gas inside a container connected to an open-end manometer is given as:
Pressure of gas = Atmospheric presure + pressure due to height
Now, we shall determine the pressure of the gas as illustrated below:
Atmospheric pressure = 0.95 atmPressure due to height = 18 cmHg = 180 mmHg = 180 / 760 = 0.24 atmPresure of gas =?Pressure of gas = Atmospheric presure + pressure due to height
Pressure of gas = 0.95 + 0.24
Pressure of gas = 1.19 atm
Thus, the pressure of the gas is 1.19 atm
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Complete question:
Please attached photo
PLEASE HELP this is due today the picture is below
Answers
Answer:
Explanation:
Ok so the first one would be Electrical energy and Radiated energy
Then the 2 question it would be not electrical but the other 3 for the 3 question it would be it would be Electrical and the radiated energy
And for the last one it would be the last 3
100 PTS IM DESPERATE NEED BY TOMMOROW
Answers
Answer:
rest will do later mom is calling me plz understand promise will do it
Explanation:
Elements and compounds are similar in that they are both made of atoms and in some cases molecules.Methods of Breaking Down CompoundsThe only way to break down a compound is through a chemical change. Sometimes, energy is needed for a chemical change to happen. Two ways to add energy to break down a compound are to apply heat and to apply an electric current.Answer:
lol
Explanation:
its 5 points
A substance freezez at -58°C. Therefore, the substance melts at
Answers
Answer:58°C
Explanation:
I believe this is the answer
What do these two changes have in common?
Answers
The burning of souse is a physical change whereas boiling sugar to make caramel is a chemical change. But both are caused by heating. Hence option C is correct.
What are chemical changes?Chemical changes involves making or breaking of chemical bonds. Whereas a physical change does not involve any bond making or breaking. The change in phase or state is a physical change.
For example, the conversion of a substance from liquid state to vapour state or solid to liquid are examples of physical changes. Whereas, chemical reaction such as combination of two reactants or decomposition results in new products by bond breaking or making or both.
These reactions are chemical changes. The boiling of sugar is a physical change. But when it is changed to caramel there occurs a chemical change since new product is formed.
Boiling sauce is also a physical change. Thus the common thing in these two situations is both are made by heating.
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Sauce burning on stove is a physical change and boiling of sugar to caramel is a example of chemical change. Both changes are caused by heating.
What is burning ?Burning is the chemical process of combustion, an object quickly combines with oxygen to produce heat. The initial material is referred to as the fuel, and the oxygen's source as the oxidizer.
However, as fire is a natural occurrence, nature has changed as a result of it. Periodic fires are beneficial to many ecosystems because they sweep out decaying organic matter; certain plant and animal populations depend on the advantages of fire for survival and reproduction.
Thus, option C is correct.
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Perform the following calculations and express the answers in
scientific notation.
a. 4.2 x 104 kg + 7.9 x 10³ kg
b. (5.23 x 106 um) (7.1 x 10-² μm)
c. 5.44 x 107 g + 8.1 x 104 mol
d. 8.40 x 105 km - 3.1 x 105 km
Answers
The answer of the calculations above in scientific notation are a=8.3 ×10³, b= 3.9 × 10^¹um, c= 1.4 × 10³gmol, d= 5.6× 10²km
Calculation to expressionsIn calculation of various expressions, the results can be expressed in a scientific notation which is a way to compress cumbersome figures.
(4.2 x 104 kg) + (7.9 x 10³ kg)4.2 × 104 = 436.8
7.9 × 10³ = 7900
436.8 + 7900 = 8,336.8
The scientific notation= 8.3 ×10³kg
(5.23 x 106 um) (7.1 x 10-² μm)5.23 x 106 um = 554.38um
554.38 × 7.1 = 3,936.1
3,936.1 × 10^-²
3.9 × 10³ × 10^-²= 3.9 × 10^¹um
The scientific notation= 3.9 × 10^¹um
5.44 x 107 g + 8.1 x 104 mol5.44 x 107 g = 582.08g
8.1 x 104 mol = 842.4 mol
582.08g+ 842.4 mol = 1,424.48
The scientific notation = 1.4 × 10³gmol
(8.40 x 105 km) - (3.1 x 105 km)8.40 x 105 km = 882km
3.1 × 105 = 325.5km
882km - 325.5km = 556.5
The scientific notation = 5.6× 10²km
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calculate the standard free energy change for the reaction shown here (298 k). what does the computed value for δg° say about the spontaneity of this process? c2h6(g)⟶h2(g) c2h4(g)
Answers
Calculating the standard free energy change (ΔG°) for the given reaction requires knowledge of thermodynamic properties, such as standard enthalpies and entropies, for the reactants and products. We get ΔG° = 0 kJ/mol.
The standard enthalpy of formation (ΔH°f) for ethene (C2H4) is ΔH°f(C2H4) = -235.1 kJ/mol. The standard enthalpy of formation (ΔH°f) for hydrogen gas (H2) is ΔH°f(H2) = -285.8 kJ/mol. The standard enthalpy of formation (ΔH°f) for carbon dioxide (CO2) is ΔH°f(CO2) = -93.9 kJ/mol.
The standard entropy of formation (ΔS°f) for ethene (C2H4) is ΔS°f(C2H4) = 177.3 J/mol·K. The standard entropy of formation (ΔS°f) for hydrogen gas (H2) is ΔS°f(H2) = 0 J/mol·K. The standard entropy of formation (ΔS°f) for carbon dioxide (CO2) is ΔS°f(CO2) = 253.2 J/mol·K.
Using the standard Gibbs free energy change formula (ΔG° = ΔH°f - TΔS°f), we can calculate the ΔG° for the given reaction:
ΔG° = ΔH°f(C2H4) + TΔS°f(C2H4) - ΔH°f(H2) - TΔS°f(H2) - ΔH°f(CO2) - TΔS°f(CO2)
ΔG° = (-235.1 kJ/mol + 273.15 kJ/mol·K) - (-285.8 kJ/mol + 273.15 kJ/mol·K) - (-93.9 kJ/mol + 273.15 kJ/mol·K) - (-253.2 kJ/mol + 273.15 kJ/mol·K)
ΔG° = 0 kJ/mol
This indicates that the reaction is at equilibrium and its standard Gibbs free energy change is zero.
The computed value for δG° does not provide information about the spontaneity of the process. Since δG° is zero, the reaction is at equilibrium and its spontaneity depends on the concentrations of the reactants and products. However, the reaction is exothermic, releasing energy, which means it is spontaneous over the entire range of concentrations that can be achieved in a closed system.
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What impacts do you think the Burmese pythons might have on local ecosystems?
Answers
Every impact in this world
PLEASE ANSWER! 5 STAR RATING - THANKS (PROFILE TOO) - BRAINLIEST IF 2 ANSWERS
A 14 V battery powers the headlights of a car. What is the resistance of the
headlights if they draw 3.0 A of current when turned on?
Answers
Answer: 9514 1404 393
4 2/3 ohms
The resistance is the ratio of voltage to current.
R = V/I
R = (14)/(3) = 4 2/3 . . . ohms
Explanation:hi ^^ have a great day hope this helps xlXCherryColaXlx (nice pfp btw)
The acceleration of a moving object can be calculated by dividing the change in velocity by the change in blank
Answers
Answer:
The acceleration of a moving object can be calculated by dividing the change in velocity by the change in TIME
Explanation:
Took the practice
An atom X that has 12 protons and 12 electrons, loses 2 electrons to form an ions, What will be the ion? What will be the number of protons and electrons in the ions?
Answers
An atom X that has 12 protons and 12 electrons, loses 2 electrons to form an ions, the charge of ion will be X⁺² the number of protons 12 and electrons in the ions is 10.
An atom X has 12 protons and 12 electrons that means X is a neutral atom and the atomic no. is 12 because total no. of protons is equal to atomic number. When it looses the 2 electrons then atom becomes positively charged ion . the charge on the ion is +2.
now, the no. of protons will be = 12
number of electrons will be = 12 - 2 = 10
Thus, An atom X that has 12 protons and 12 electrons, loses 2 electrons to form an ions, the charge of ion will be X⁺² the number of protons 12 and electrons in the ions is 10.
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what type of land use can result in nutrient depletion
Answers
3. Assertion (A): There is a small gap left between the rails of a railway track
Reason (R): Cooling of substances result in contraction.
Both A and R are true but R is not the correct explanation of A
A is false but R is true
b.
c. A is true but R is false
d. Both A and R are true and R is the correct explanation of A
Answers
There is a small gap left between the rails of a railway track Reason (R): Cooling of substances result in contraction. Both A and R are true but R is not the correct explanation of A,
Why cooling causes contraction ?When a substance is cooled, it means that the heat is removed from the substance. This results in fewer excited molecules and, as a result, less random motion. The force of attraction increases, resulting in fewer spaces between molecules, which causes contraction.
Why there is appearance of gap between railway track?The gaps left between successive rails on a railway track as a result of the rails expanding in the summer. The gap exists to allow for this expansion. If no gap is left, the summer expansion will cause the rails to bend sideways. This will lead to train accidents.
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