The heating curve below shows the temperature change that occurs as a solid is heated. What is occurring at segment DE of the graph?
Melting
freezing
boiling
Answers
At point A- We are adding temperature, from A-B we are just heating the solid molecules, from point B-C, temperature is not changing but time is elapsing(solid is melting). At Point C its completely in liquid state. From point D to E liquid molecules start to heat up and evaporation occurs. From point E-F we are just heating steam.
Related Questions
Which macromolecules were present in the milk?
Answers
hope it helps.
How many molecules of carbon dioxide are there in 44.0 grams of the gas? (atomic mass of carbon = 12.0 and atomic mass of oxygen = 16.0)
Answers
Avogadro's number is the number of units (atoms, molecules) in 1 mole of substance:
6.023 × 10²³ molecules per 1 moleLet's calculate how many grams are in 1 mole. This is expressed as molar mass Mr:
Mr(CO2) = Ar(C) + 2Ar(O)
Ar(C) = 12
Ar(O) = 16
Mr(CO2) = 12 + 2 * 16 = 12 + 32 = 44 g
There are 44 g in 1 mole.
There are 6.023 × 10²³ molecules in 1 mole.
So there are 44 g in 6.023 × 10²³ molecules
What is a renewable source of energy? a. An energy resource that is used up over time. b. An energy resource that is available and can be recreated. c. An energy resource that is no longer used. d. An energy resource that is now used more than oil and gas.
Answers
The correct answer would be B
The diffusion of water molecules across a selectively permeable membrane from an area of higher concentration to an area of lower concentration is
Answers
in a particular redox reaction, Cr is oxidized to CrO42- and Ag+ is reduced to Ag. Complete and balance the equation for this reaction in acidic solution.
Answers
Answer:
The complete and balance the equation for this reaction in acidic solution is given by:
[tex]Cr+4H_2O+6Ag^+\rightarrow CrO_4^{2-}+8H^++6Ag[/tex]
Explanation:
Oxidation reaction of chromium to chromate in acidic medium:
[tex]Cr\rightarrow CrO_4^{2-}[/tex]
Add 4 molecules of water on the left hand side to balance the oxygen:
[tex]Cr+4H_2O\rightarrow CrO_4^{2-}[/tex]
Now balance hydrogen atoms by adding hydrogen ions on opposite to the side where water molecule are present .
[tex]Cr+4H_2O\rightarrow CrO_4^{2-}+8H^+6e^-[/tex]....[1]
In last, to balance the charge on the both sides add electrons to sides where positive charge is more.
Reduction reaction of silver ions to silver in acidic medium:
[tex]Ag^++e^-\rightarrow Ag[/tex]..[2]
By [1] + 6 × [2] , we will get the balance equation for this reaction in acidic solution:
[tex]Cr+4H_2O+6Ag^++6e^-\rightarrow CrO_4^{2-}+8H^+6e^-+6Ag[/tex]
[tex]Cr+4H_2O+6Ag^+\rightarrow CrO_4^{2-}+8H^++6Ag[/tex]
Which of the following characteristics of carbon is responsible for the variety of carbon-based molecules on Earth?
A) It can form bonds.
B) It can form proteins.
C) It has four valence electrons.
D) It is organic in nature.
...?
Answers
Carbon is responsible for the variety of carbon-based molecules on Earth because it is organic in nature.
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What is the most appropriate unit of astronomical distance to represent the distance between an earth an orbiting space station and neptune?
Answers
Final answer:
The astronomical unit (AU) is the most appropriate unit to represent the distance between an Earth-orbiting space station and Neptune.
Explanation:
The most appropriate unit of astronomical distance to represent the distance between an Earth-orbiting space station and Neptune is the astronomical unit (AU). The AU is defined as the average distance from Earth to the Sun and is approximately 150 million kilometers or 93 million miles. It provides a convenient scale for measuring distances within our solar system, avoiding the use of very large numbers that would be involved if the kilometer were used instead. When discussing the distance between Neptune and an orbiting space station, it's important to remember that Neptune is about 30 AU from the Sun. This puts it at a vastly greater distance from the orbiting space station than the Moon or even other planets within the inner solar system.
Use the following equation to complete the questions below. 2C2H6 + 7O2 → 4CO2 + 6H2O How many moles of oxygen would you need to produce 25 moles of CO2? How many moles of water would be produced if you used 32 moles of O2?
Answers
Small polar molecules, such as water and ethanol, pass through the membrane slowly because of a process called
Answers
Water and ethanol can pass through the membrane even though it's polar because it's a very small molecule and can under go this process through osmosis.
What is Osmosis ?A process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.
Water can also pass through the cell membrane by osmosis, because of the high osmotic pressure difference between the inside and the outside the cell.
This is not an easy process, because the solubility of water and Ethanol in lipid is about 1 molecule of water per million molecules of lipid.
But, the outside concentration of water or ethanol becomes very high (about 50 mol/L), and the surface area to volume ratio of the cell is very large, so this is an important cellular process.
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How do you determine the frequency of light whose wavelength is 4.257x10^-7?
Answers
frequency = velocity/wavelength
= (3*10^8)/(4.257*10^-7)
= 7.047*10^14
What is the empirical formula for a compound if a sample contains 1.0 g of S and 1.5 g of O?
SO
SO3
S2O2
S2O3
Answers
let's assume that 1 Arbitrary unit of sulfur is 1g heavy. this would mean that 2 units of Oxygen is 1g heavy(since it's half as heavy as S when comparing equal number of atoms). since we have 1.5g of oxygen, so there are 1.5*2=3 units of oxygen in that sample. and there are 1*1=1 units of Sulfur in that sample.
therefore the empirical formula is SO3
Moles O₂ = 1.5/32
simplest ratio = 1 : 1.5
= 2:3
Thus, empirical formula:
S₂O₃
The fourth option is correct.
A material will float on the surface of a liquid if the material has a density less than that of the liquid. Given that the density of water is approximately 1.0 g/mL, will a block of material having a volume of 1.2 x 10^4 in^3 and weighing 350 lb float or sink when placed in a reservoir of water?
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What is the difference between a molecule and a compound?
Answers
Example of molecule: H2 (molecular hydrogen); it has two hydrogen atoms
-A compound IS a molecule that consists of two different types of elements
Example of compound: H2O (water); it has two hydrogen atoms and one oxygen atom
Ammonia is _____.
an acid
a base
a neutral
Answers
So, option B is your answer.
Hope this helps!
Ammonia is a base! Have a blessed day!
-Steel jelly
What is the name of a solution whose concentration of solute is equal to the maximum concentration that is predicted from the solute's solubility?
dilute
saturated
unsaturated
supersaturated
Answers
Answer: The correct answer is saturated solution.
Explanation:
For the given options:
Dilute solutions are defined as the solutions in which solute particles are present in less very amount than the solvent particles.
Unsaturated solutions are defined as the solutions where more and more of solute particles can be dissolved in the given amount of solvent.
Saturated solutions are defined as the solutions where no more solute particles can be dissolved in the solvent. The concentration of the solute particles that can be dissolved in a solution is maximum.
Supersaturated solutions are defined as the solutions where more amount of solute particles are present than the solvent particles.
From the above information, we conclude that the given solution is saturated solution.
Answer:
The correct answer is saturated
Explanation:
Hello!
Let's solve this!
Diluted solutions are when you have more solvent than solute.
The saturated solution is when it has the same amount of solute as of solvent.
The unsaturated solution is the solution in which the solvent can still receive more solute.
The supersaturated solution is when it has more solute than the one that can dissolve the solvent.
Then the correct answer is saturated where the solvent already has the maximum amount of solute that can dissolve.
Why do elements in the same group have a similar reactivity?
Answers
What kind of bond holds together atoms within a molecule?
Answers
The bond holds together atoms within a molecule is ionic bonds, covalent bonds and metallic bonds.
There are three main types of chemical bonds that hold atoms together within a molecule:
1. Ionic bonds are formed when one atom donates electrons to another atom. The atom that donates electrons becomes a positively charged ion, and the atom that receives electrons becomes a negatively charged ion. The oppositely charged ions are attracted to each other by the electrostatic force.
2. Covalent bonds are formed when two atoms share electrons. The shared electrons are attracted to the nuclei of both atoms, which holds the atoms together. Covalent bonds can be either polar or nonpolar. Polar covalent bonds occur when the atoms share the electrons unequally, while nonpolar covalent bonds occur when the atoms share the electrons equally.
3. Metallic bonds are formed when metal atoms share their valence electrons with each other. The valence electrons form a "sea" of electrons that surrounds the metal atoms. The metal atoms are attracted to the sea of electrons, which holds the atoms together.
The type of bond that holds atoms together in a molecule depends on the elements that make up the molecule and the electronegativity of the atoms. Electronegativity is a measure of how strongly an atom attracts electrons. Atoms with high electronegativity tend to form ionic bonds, while atoms with low electronegativity tend to form covalent bonds.
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Which statement correctly describes a chemical reaction?
1)Reactants come out of a reaction.
2)Energy is always released.
3)Bonds between atoms break and new bonds form.
4)Products go into a reaction.
Answers
The substance (or substances) initially involved in a chemical reaction are called reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more products, which usually have properties different from the reactants.
I hope my answer has come to your help. God bless and have a nice day ahead!
How many moles of oxygen atoms in one mole of CO2
Answers
1 mole of carbon and 2 moles of oxygen combined to form a compound. For every one atom of carbon there are two atoms of oxygen. The formula could be CO2.
Which types of matter are made of atoms?
A. solids only
B. solids and liquids only
C. plasma only
D. solids, liquids, gases and plasma
...?
Answers
Solids, liquids, gases and plasma are all made of atoms.
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Scientist call an organism that has two different alleles for a trait
Answers
In writing the complete ionic equation for the reaction (if any) that occurs when aqueous
solutions of KOH and Mg(NO3)2 are mixed, which of the following would not be
written as ionic species?
A) KOH
B) Mg(NO3)2
C) Mg(OH)2
D) KNO3
E) All of the above would be written as ionic species.
Answers
4NH3 + 5O2 4NO +6H2O
In an experiment, 3.25 g of NH3 are allowed to react with 3.50 g of O2. How many grams of NO are formed?
Please round final answers to the tenth position, one place after the decimal
Answers
[tex]\boxed{2.6264752{\text{ g}}}[/tex] of NO is formed during the given reaction.
Further explanation:
Limiting reagent is the species or reagent in a chemical reaction according to which the amount of product is decided. It is completely consumed in the reaction.
Stoichiometry governs the amount of species present in the reaction by using the relationship between reactants and products.
The given reaction is as follows:
[tex]{\text{4N}}{{\text{H}}_3} + {\text{5}}{{\text{O}}_2} \to {\text{4NO}} + 6{{\text{H}}_{\text{2}}}{\text{O}}[/tex]
The formula to calculate the moles of the substance is as follows:
[tex]{\text{Moles of substance}} = \dfrac{{{\text{Given mass of substance}}}}{{{\text{Molar mass of substance}}}}[/tex] ...... (1)
Substitute 3.25 g for the given mass and 17.03 g/mol for the molar mass in equation (1) to calculate the moles of [tex]\text{NH}_3[/tex].
[tex]\begin{aligned}{\text{Moles of N}}{{\text{H}}_3} &= \left( {\frac{{{\text{3}}{\text{.25 g}}}}{{17.03{\text{ g/mol}}}}} \right)\\&= 0.1908{\text{ mol}}\\\end{aligned}[/tex]
Substitute 3.50 g for the given mass and 31.98 g/mol for the molar mass in equation (1) to calculate the moles of [tex]\text{O}_2[/tex].
[tex]\begin{aligned}{\text{Moles of }}{{\text{O}}_2} &= \left( {\frac{{{\text{3}}{\text{.50 g}}}}{{{\text{31}}{\text{.98 g/mol}}}}} \right)\\&= 0.1094{\text{ mol}}\\\end{aligned}[/tex]
According to the stoichiometry of this reaction, four moles of reacts with five moles of [tex]\text{O}_2[/tex] to form four moles of NO and six moles of [tex]\text{H}_2\text{O}[/tex].
Calculate the moles of [tex]\text{O}_2[/tex] that react with and 0.1908 moles of [tex]\text{NH}_3[/tex] as follows:
[tex]\begin{aligned}{\text{Amount of }}{{\text{O}}_2} &= \left( {{\text{0}}{\text{.1908 mol N}}{{\text{H}}_3}} \right)\left( {\frac{{{\text{5 mol }}{{\text{O}}_2}}}{{4{\text{ mol N}}{{\text{H}}_3}}}} \right)\\&= 0.2385{\text{ mol }}{{\text{O}}_2}\\\end{aligned}[/tex]
The above calculations concluded that 0.2385 moles of [tex]\text{O}_2[/tex] are needed to react with 0.1908 moles of [tex]\text{NH}_3[/tex] but only 0.1094 moles of [tex]\text{O}_2[/tex] are present in the reaction mixture. Therefore, [tex]\text{O}_2[/tex] is present in limited quantity and is a limiting reagent.
Since [tex]\text{O}_2[/tex] comes out to be the limiting reagent, the formation of NO is governed by it. According to the reaction stoichiometry, five moles of [tex]\text{O}_2[/tex] produces four moles of NO. Therefore the amount of NO can be calculated as follows:
[tex]\begin{aligned}{\text{Amount of NO}} &= \left( {0.1094{\text{ mol }}{{\text{O}}_2}} \right)\left( {\frac{{4{\text{ mol NO}}}}{{5{\text{ mol }}{{\text{O}}_2}}}} \right)\\&= 0.08752{\text{ mol}}\\\end{aligned}[/tex]
Rearrange equation (1) to calculate the mass of the substance.
[tex]{\text{Mass of substance}}= \left( {{\text{Moles of substance}}} \right)\left( {{\text{Molar mass of substance}}} \right)[/tex] ...... (2)
Substitute 0.08752 mol for the moles and 30.01 g/mol for the molar mass in equation (2) to calculate the mass of NO.
[tex]\begin{aligned}{\text{Mass of NO}} &= \left( {0.08752{\text{ mol}}} \right)\left( {30.01{\text{ g/mol}}} \right)\\&= 2.6264752{\text{ g}}\\\end{aligned}[/tex]
Learn more:
Calculate the moles of chlorine in 8 moles of carbon tetrachloride: https://brainly.com/question/3064603 How many grams of potassium was in the fertilizer? https://brainly.com/question/5105904
Answer details:
Grade: Senior School
Chapter: Mole concept
Subject: Chemistry
Keywords: limiting reagent, NH3, NO, H2O, O2, 2.6264752 g, moles, mass, molar mass.
Which observation would best support that the bond present was a covalent bond?
Answers
Answer:
A covalent bond is present between two non-metals that share electrons in their molecular structure.
Explanation:
Examples of covalent bonds may be between carbon dioxide or water. And there may be three types of covalent bonds such as ionic, covalent and polar. In the first type, there is a transfer of an electron resulting in a gain for one of the atoms. In the second type, there is a sharing of electrons between the atoms. The third type is characterized by a difference in electronegativity between atoms.
Answer: carbon and oxygen share pairs of valence electrons
Explanation: its self explanatory
What does ozone do to make life on earth possible?
Answers
Reasoning - Without the ozone layer the whole planet would have a loss of water and especially people burning very easily from the sun.
which solution has a molality of 0.25m NaCl?
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A substance with equal numbers of H+ ions and OH- ions is a basic solution.
True
False
Answers
Answer: False
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
Acids have pH ranging from 1 to 6.9, bases have pH ranging from 7.1 to 14 and neutral solutions have pH equal to 7.
[tex]pH=-\log [H^+][/tex]
[tex]pOH=-\log[OH^-][/tex]
When the concentration of [tex][H^+]=[OH^-][/tex], the solution is neutral, [tex]H^+[/tex]> [tex]OH^-[/tex] , the solution is acidic and if [tex]H^+[/tex]< [tex]OH^-[/tex] , the solution is basic.
What is the definition of the term salt??
Answers
What are the products of the double-replacement reaction between potassium bromide and silver nitrate? Name the resulting compounds.
Answers
Answer: The products formed are potassium nitrate [tex](KNO_3)[/tex] and silver bromide ( AgBr ).
Explanation: Double replacement or double displacement reactions are the reactions in which the positive ions and negative ions of the two reactants interchange to form the products. These reactions are carried out on the basis of their position in reactivity series.
The elements lying above in the reactivity series will be able to displace the elements that lie below in the reactivity series.
For the reaction of potassium bromide and silver nitrate, the reaction follows:
[tex]KBr(aq.)+AgNO_3(aq.)\rightarrow AgBr(s)+KNO_3(aq.)[/tex]
The resulting products are potassium nitrate [tex](KNO_3)[/tex] and silver bromide ( AgBr ).
What is the abreviation for carbon dioxide??
Answers
The abbreviation for carbon dioxide is CO₂, which represents its chemical composition of one carbon atom and two oxygen atoms.
Explanation:The abbreviation for carbon dioxide is CO₂. This is derived from the chemical formula for carbon dioxide, which includes one carbon atom (C) and two oxygen atoms (O₂). This formula reflects the compound's composition and is used commonly in chemistry to denote different substances.
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