Earth is made mostly of metals and rocks. the elements (carbon, silicon, iron, etc.) that make up these materials form, and they were produced by nuclear fusion in stars.
Metals are materials that, when freshly worked, polished, or crushed, have a lustrous appearance and are relatively good conductors of electricity and heat. Metals are typically ductile and malleable. These properties are the result of metallic bonding between the atoms or molecules of the metal.
Metal is very useful material. Metals have many properties such as B. Strength, toughness, and stiffness. When heated, the metal can be shaped into anything from tiny paper clips to giant airplanes. It is also an excellent conductor of electricity and heat, making it useful for electricity and cooking pots.
Learn more about metals here
https://brainly.com/question/25597694
#SPJ4
A first-order reaction that results in the destruction of a pollutant has a rate constant of 0.1/day. how many days will it take for 68 percent of the chemical to be destroyed?
In a first-order reaction, it takes 23.02 days for 68 percent of the chemical to be destroyed.
Given,
fee constant for the destruction of pollutant = 0.1/day
We ought to discover the number of days it'll take for sixty eight percent of the chemical to be destroyed.
[A] = [A]₀e^⁻kt
in which [A] is the present awareness, and
[A]₀ is the initial awareness
k is the price of decrement
[A]₀ = 1
[A] = 0.1
Or, t =㏑(10)/k
Or, t = 2.302/zero.1
Or, t = 23.02 days.
for this reason the wide variety of days required for the destruction of sixty eight percent of chemicals is 23 days.
To learn more about the first-order reaction, visit: https://brainly.com/question/10898529
#SPJ4
A particular vitamin's chemical formula has one cobalt atom. What is the molar mass of the vitamin if it contains 4.34% cobalt?
The molar mass of vitamin if it contains 4.34% of cobalt is 1358 g/mole.
How is molar mass calculated?
Molar mass is the mass of 1 mole of the compound.One mole of compound contains Avogadro's number of molecules.So,molar mass is mass of Avogadro's number of molecules.
Molar mass is also defined as mass of the sample divided by the amount of substance, measured in moles .It is a bulk quantity not a molecular property of substance. The SI unit of molar mass is kilogram per mole.
In this problem,vitamin has 1 cobalt atom .The atomic mass of cobalt is 58.93 g/mole.So according to the definition,mass of 1 mole of cobalt is 58.93 g =4.34% mass of 1 mole of vitamin.
To find 100% mass of 1 mole of vitamin
58.93/4.43×100=1358 g
Hence,the molar mass of vitamin is 1358 g.
To learn more about molar mass click here:
https://brainly.com/question/13152455
#SPJ1
Proton a couples to proton b. proton a posseses a j-value of 3.0 hz. what do you expect the j-value proton b posseses to be? (1 pt)
Proton a couples to proton b. proton a possesses a j-value of 3.0 Hz. the j-value proton b possesses to be 3.0hz.
A proton contains two up quarks and one down quark. A neutron contains one up quark and two down quarks. The core is held together by one of four fundamental forces, the "strong nuclear force" (gravitational and electromagnetic forces are the other two). Heavy atoms tend to have more neutrons than protons, but the number of electrons in the atom is always equal to the number of protons. Therefore, the atom as a whole is electrically neutral.
There are two types of protons and neutrons: up quarks and down quarks. Each up quark has a +2/3 charge. Each down quark has a charge of -1/3. The sum of the charges of the quarks that make up the nuclear particle determines its charge.
Learn more about proton here
https://brainly.com/question/1805828
#SPJ4
Solution of known concentration that is slowly added to a solution of unknown concentration.
A solution of known concentration that is slowly added to a solution of unknown concentration is called titrant.
Titration is the steady addition of a known concentration solution (called a titrant) to a known volume of an unknown concentration solution until the reaction approaches neutralization, which is sometimes indicated by a color change.
Until the reaction is complete, the analyte (the unknown solution) is normally added in a known amount to the titrant (the known solution) through a buret. Knowing the volume of titrant added allows the concentration of the unknown to be calculated. An indicator is often used to indicate the reaction's endpoint or end of reaction.
Therefore, titration is a technique used to determine the concentration of an unknown solution.
Read more about Titration:
https://brainly.com/question/16254547
#SPJ4
An amino acid consists of an amino group at one end and which group at the opposite end?
Answer:
Carboxylic acid group
Explanation:
Carboxylic acid and amine groups form the basis of an amino acid. One group reacts with the other group on a neighboring amino acid to form the peptide bond, with the release of a water molecule.
Given what you know of the acid base chemistry of hf, what is the concentration of hf in an aqueous solution with a ph of 5.89?
Hydrofluoric acid, HF in an aqueous form having molecular weight of 20.01 have concentration of 48-50% w/w in aqueous solution/water with a pH of 5.89.
HF in an aqueous solution ionizes like the other acids. It is extremely corrosive. It dissociates in water as -
HF + H₂O ⇆ H₃O⁺ + F⁻
Hydrofluoric acid is much stronger when concentrated. If concentration increases and approach to 100%, the acidity of acid increases and the base forms a bond.
3HF ⇆ H₂F⁺ + HF₂⁻
The presence of hydrogen ion in an aqueous solution makes the HF acidic. HF is soluble with boiling point 19.5°C and melting point 0f -83.6°C
To learn more about HF,
brainly.com/question/3102869
#SPJ4
Consider the following: you mix 7.60 ml of ( = 1.492 g/ml) and 6.50 ml of ( = 2.890 g/ml), giving 14.1 ml of solution. what is the density of this mixture?
The 14.1 ml solution has a density of 2.1365 g/ml.
Density is defined as the ratio between the mass of a substance and the volume it occupies. Denoted by ρ, density is mass per unit volume and the formula is given below:
ρ = mass / volume
To solve for the density of a mixture or solution of two substances with different densities, the mass and volume of each substance must be known, as:
ρ mix = (M1 + M2) / (V1 + V2)
The volume and densities of the two given substances are known and can be used to solve for the unknown mass of each substance.
M1 = ρ x V1
M1 = 1.492 g/ml x 7.60 ml
M1 = 11.3392 g
M2 = ρ x V2
M2 = 2.890 g/ml x 6.50 ml
M1 = 18.785 g
Solving for the density of the mixture,
ρ mix = (M1 + M2) / (V1 + V2)
ρ mix = (11.3392 g + 18.785 g) / (7.60 ml + 6.50 ml)
ρ mix = 30.1242 g / 14.1 ml
ρ mix = 2.1365 g/ml
To learn more about density of mixtures: https://brainly.com/question/28037379
#SPJ4
Which food contains at least 100 mcg of folate per serving? one, some, or all responses may be correct.
One-half cup of black-eyed peas contains at least 100 mcg of folate per serving.
In infants and the women with poor folic acid intakes, the neural tube defects (NTDs), or failures in the closure of the neural tube are more common. For the normal formation of the spinal cord, proper closure of the neural tube is required.
Within the first month of gestation, the neural tube begins to close, often before a person realizes that she is pregnant.
Therefore, 0.4 mg of folic acid should be taken every day, while consuming dietary sources of folate, i.e. intake of folate rich diet/meal by all people who are capable of becoming pregnant.
One-half cup of black-eyed peas contains at least 100 mcg of folate. Ready-to-eat breakfast cereal contains 200 mcg of folate and a slice of bread contains 20 mcg, and not 100 mcg of folate. One-half cup of broccoli and a cup of pasta contain 50 mcg, not 100 mcg of folate.
Complete question is-
Which food contains at least 100 mcg of folate per serving? one, some, or all responses may be correct.
1. Bread
2. Broccoli
3. Cooked pasta
4. Black-eyed pasta
5. Ready-to-eat breakfast cereal
To learn more about folate,
brainly.com/question/10228312
#SPJ4
True or false: Chemical properties can be observed only when the substances in a sample of matter are changing into different substances.
According to the bohr model, what is the energy change in joules that occurs when an electron falls from the n = 4 to the n = 2 energy level in a hydrogen atom?
According to the bohr model, the energy change in joules that occurs E=−1.36×10∧−19J, when an electron falls from the n = 4 to the n = 2 energy level in a hydrogen atom.
What is bohr model ?The Bohr model, also known as the Rutherford-Bohr model, was first proposed by Niels Bohr and Ernest Rutherford in 1913 and describes an atomic system with an orbiting system of electrons and a small, dense nucleus that is similar to the Solar System in structure but is attracted by electrostatic forces rather than gravity.
1) The orbits of the electrons surrounding the nucleus are circular and have a constant energy.
2) The electron only rotates in orbits with angular momentum greater than or equal to nhi/2π³.
Only when an electron transitions from one orbit to another can energy become realised or absorbed in the form of a photon.
To learn more about bohr model go to -
https://brainly.com/question/4138548
#SPJ4
When nad becomes nadh, it is being? oxidized and releasing chemical energy. reduced and gaining chemical energy. oxidized and gaining chemical energy. reduced and releasing chemical energy.
When NAD becomes NADH, it is being reduced and gaining chemical energy.
Nicotinamide adenine dinucleotide (NAD), a coenzyme, can exist in two forms, NAD⁺ (oxidized) and NADH (reduced form).
Electrons and protons released in catabolism reactions are attached to NAD⁺. The conversion of NAD⁺ to NADH is important reaction for production of ATP during the cellular respiration.
Reduction is lowering oxidation number because element, ion or compound gain electrons.
Chemical equation for reaction of reduction of NAD⁺ (see picture below):
NAD⁺ + 2e⁻ + H⁺ → NADH
Nicotinamide adenine dinucleotide (NAD) is made of two nucleosides joined by pyrophosphate.
More about reduction :brainly.com/question/25334331
#SPJ4
points
Sodium and chlorine react together to form sodium chloride. Identify the reactant(s) and product(s?
Sodium and chlorine are the two reactants and sodium chloride is the product.
A very reactive metal called sodium interacts with chlorine gas to form sodium chloride, an inert salt. Chlorine gas is reduced to chloride anions whereas sodium is oxidized to sodium cation (Na+) (Cl-).One mole of sodium and two moles of chlorine gas combine to form two moles of sodium chloride.We are aware that chlorine is a very reactive non-metal and that sodium is a very active metal. Typically, non-metals like halogens tend to receive electrons while metals prefer to expel electrons.Chlorine accepts the electron to create the anion Cl-, and sodium rapidly loses its final shell electron to produce the cation Na+.Sodium, a solid reactant, interacts with greenish-yellow gaseous chlorine to form white crystalline sodium chloride.
Therefore, sodium and chlorine are reactants whereas sodium chloride is the product.
Learn more about chemical reactions:
https://brainly.com/question/11231920
#SPJ9
When 2.16g of mercuric oxide is heated, it decomposes to yield 2.00g of mercury and 0.16g of oxygen. which law is supported by this experiment?
The experiment described in the question given above supports the law of conservation of mass.
What is Decomposition?In chemistry, decomposition may be defined as a type of chemical reaction through which one reactant molecule significantly breaks down into two or more product molecules.
The same concept is applied in the question as well where the heating of mercuric oxide produces mercury and oxygen. According to the question, the mass of the reactant is equal to 2.16g, while the mass of the product is equal to 2.00 g plus 0.16 g which is togetherly 2.16 g.
Therefore, the experiment described in the question given above supports the law of conservation of mass.
To learn more about the Law of conservation of mass, refer to the link:
https://brainly.com/question/19038178
#SPJ4
Find the volume of a liquid if 32.5 g of the liquid has a density of 0.852 g/mL.
Answer: 27.69 mL^3
Explanation:
32.5 g * 0.852 g/mL=
32.5*0.852=27.69 mL^3 ==>Volume is expressed in units cubed.
According to bohr's model, when does an electron emit electromagnetic radiation?
According to Bohr's model, electron emit electromagnetic radiation when an electron moves from the higher energy orbit to the lower energy orbit of an atom.
Niels Bohr (1885–1962) proposed a model for the hydrogen atom that explained its atomic emission spectrum.
According to the Bohr model of the atom:
1. Energy levels of electrons are discrete (certain discrete values of energy), that is why hydrogen shows discrete, bright, colored lines.
2. Electrons orbit the nucleus in orbits that have a set size and energy.
3. Electrons can jump from one energy level to another, absorbing or emitting electromagnetic radiation with a frequency ν (energy difference of the levels).
More about Bohr's model: brainly.com/question/18002213
#SPJ4
Why do we emphasize the valence electrons in an atom when discussing atomic properties?
We emphasize the valence electrons in an atom when discussing atomic properties, as they are most accessible to other atoms.
What are valence electrons?The valence electrons are the electrons that are present in the outer shell of the atoms. These electrons are free for making bonds with the electrons of other atoms.
Electrons are joined with other electrons to make a compound. These electrons are shared by or gained by other atoms.
Thus, when discussing atomic qualities, we focus on the valence electrons in an atom since they are the most receptive to other atoms.
To learn more about valence electrons, refer to the link:
https://brainly.com/question/13993867
#SPJ4
A central theme in chemistry is that we study ______ changes in matter to understand their ______ causes.
A central theme in chemistry is that we study Observable changes in matter to understand their Unobservable causes.
Matter is a substance made up of a variety of sorts of particles that occupies physical house and has inertia. According to the standards of current physics, the a variety of sorts of particles every have a particular mass and size. The most acquainted examples of fabric particles are the electron, the proton and the neutron.
Learn more about Matter here:
https://brainly.com/question/4513444
#SPJ4
scientific process how can a casual question be answered 3 hypotheses water experiment
There are 3 experiments which helps to under water evaporation system.
Both the temperature of the air surrounding the water and the rate of evaporation increased. In the second experiment, we observed an increase in air flow around the water, and this time, the rate of evaporation increased as well. In the third and final experiment, we observed an increase in the amount of light in the room, and this time, the rate of evaporation increased as well.Because the kinetic energy of a substance can be measured by its temperature, increasing in the temperature or kinetic energy of the air around water will also increase the kinetic energy of the water, which will increase the rate of evaporation.It's crucial to have good air flow since it drives water droplets in the air away from you, reducing the amount of humidity in the region. Because there will then be space for the evaporated air or space for the evaporated water to flow into the air, it will then be simpler for the water to really evaporate.Water in the presence of sunlight is given extra energy, which increases evaporation.Learn more about Evaporation here:
https://brainly.com/question/24258
#SPJ9
An instrument can determine the half-life of an element with a 0.8% error. Radon-220 has a half-life of 52 s. What is the absolute error that could be expected measuring the half-life of radon-220?
The absolute error that could be expected when measuring the half-life of radon-220 is 0.416 s
Data obtained from the questionThe following data were obtained from the question:
Percentage error = 0.8%Actual measurement = 52 sAbsolute error =?How to determine the absolute error in measuring the half-lifeWe can obtaine the absolute error as illustrated below:
Percentage error = (Absolute error / Actaul measurement) × 100
0.8% = Absolute error / 52
0.008 = Absolute error / 52
Cross multiply
Absolute error = 0.008 ×52
Absolute error = 0.416 s
Thus, the absolute error in measuring the half-life is 0.416 s
Learn more about error:
https://brainly.com/question/24202332
#SPJ1
At which bond would water need to be added to achieve hydrolysis of the peptide, back to its component amino acid?
The peptide bond is broken by the hydrolysis of water. The hydrogen ion of water goes to the -NH end (shown to the right of bond C) and the hydroxyl Ion of water goes to the -CO ends (shown to the left of bond C), resulting in the breakdown of peptide Bond and formation of individual amino acid.
The reaction of water with another compound forms two or more products. Some examples of hydrolysis include dissolving salts of weak acids or weak bases in water or dissolving sulfuric acid in water to form hydronium and bisulfate compounds.
The difference between hydration and hydrolysis is that hydrolysis is the process of breaking a bond with water whereas hydration is defined as an electrophilic addition reaction without breaking the original molecule. During hydration, water molecules are added to the substance. A chemical decomposition process that involves breaking bonds and adding hydrogen cations and hydroxide anions of water.
Learn more about hydrolysis here
https://brainly.com/question/4352413
#SPJ4
What is the definition of Buffer solution !!
Answer:
a solution which resists changes in pH when acid or alkali is added to it is known as Buffer solution
A tetrahedral carbon is ____________ hybridized while a linear carbon is ____________ hybridized.
A tetrahedral carbon is sp3 hybridized while a linear carbon is sp hybridized.
Carbon is a chemical element with the symbol C and atomic number 6. It is a non-metal and is tetravalent. That atom donates four electrons to form a covalent chemical bond. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025% of the Earth's crust.
Carbon is an essential element for all life forms on earth. Carbon uptake and release are part of all plant and animal life, whether these life forms take up carbon to help make food or release carbon as part of respiration. Carbon is constantly moving from place to place. Carbon is also found in fossil fuels such as petroleum (crude oil), coal, and natural gas. Carbon is also found in dead, decaying animals and animal waste soils. Carbon is stored in the biosphere of plants and trees.
Learn more about carbon here
https://brainly.com/question/141693
#SPJ4
The action potentials of myocardial autorhythmic cells, are due to a combination of increasing Na+ and Ca2+ ________ and decreasing k ________.
The action potentials of myocardial autorhythmic cells, are due to a combination of increasing Na⁺ and Ca²⁺ influx and decreasing K⁺
efflux .
The autorythmic cells are concentrated in many areas such as:
Sinoatrial (SA) node which is located in the upper wall of the right atrium (auricle). It initiates the cardiac cycle by generating an action potential spreading throughout both atrium via gap junctions of the cardiac muscle fibers.
These autorhythmic cells have unique ability to depolarize spontaneously, which results in a pacemaker potential. Channels of cardiac autorhythmic cells are responsible for the electrical signal that triggers heart contraction.
Autorhythmic cells begin depolarizing due to a slow continuous influx of Na⁺ and Ca²⁺, and a reduced efflux of K⁺.
Several protein channels are embedded in the plasma membrane of an autorhythmic cell that allows ions to move in and out of the cell. These are important for generating action potential.
Sodium channels : allow Na⁺ ions to enter cellFast calcium channels : allow Ca²⁺ ions to enter cellPotassium channels : allow K⁺ ions to leave the cellTo learn more about autorhythmic cells,
https://brainly.com/question/15517377
#SPJ4
How many protons neutrons and electrons are there in a neutral atom of ^60co cobalt-60?
The protons neutrons and electrons are there in a neutral atom
In a neutral atom of ⁶⁰Co (cobalt-60), there are 27 protons, 27 electrons, and 33 neutrons.
We have to find the number of protons, neutrons, and electrons in a neutral atom of ⁶⁰Co (cobalt-60).
The number of protons = The atomic number.
The atomic number of cobalt is = 27
Therefore, the protons are 27
As protons and electrons are equal. Then, the number of electrons is 27.
The number of Neutrons = Atomic number - Number of protons.
Neutrons = 60 - 27
Or, neutrons = 33
Hence, the number of neutrons is 33, electrons are 27, and protons are 27 in a neutral (cobalt-60).
To learn more about neutrons, protons, and electrons, visit: https://brainly.com/question/11691497
#SPJ4
Why does the first ionization energy generally increase across a period for the main group elements?
Ionization energy : the minimum amount of energy demands to detach an electron from an isolated atom.
Ionization energy also known as potential energy.
The charge of the nucleus increases from side to side in a row and so there is an increase in the attraction in the middle of the nucleus and the surrounding electrons. As we move from side to side in a periodic table from left to right, the nuclear charge increases. This is because of increasing nuclear charge, which concludes in the topmost electron being more strongly leap to the nucleus.
To know more about Ionization energy here :
https://brainly.com/question/16243729?referrer=searchResults
#SPJ4
Consider an atom of zirconium which has a mass number of 96.how many electrons are in an atom of zirconium with a charge of 3?
An atom of zirconium which has a mass number of 96 has 37 electrons in it.
What is zirconium?Atomic number 40 and the letter Zr are used to identify the chemical element zirconium. Zircon is the name of the mineral from which zirconium gets its name. The name has a connection to the most significant source of zirconium, the Persian word zargun (zircon; zar-gun, "gold-like" or "like gold").
This transition metal closely resembles titanium and, to a lesser extent, hafnium. It is glossy, grey-white, and strong. Although it is used sparingly as an alloying agent due to its high corrosion resistance, zirconium is mostly utilised as a refractory and an opacifier.
Inorganic and organometallic compounds like zirconium dioxide and zirconocene dichloride are both formed by zirconium. There are five stable isotopes that are found in nature. The biological function of zirconium compounds is unknown.
Learn more about zirconium
https://brainly.com/question/1347130
#SPJ4
Which of the following demonstrates a chemical change? (1 point)
• dry ice vaporizing
•
iron (Fe) reacting to water((H,O)) and
oxygen(O) to form iron oxide(Fe2Og)
O sugar and water mixing to create sugar water
• steam condensing on a mirror
The reaction that demonstrates a chemical change is iron (Fe) reacting to water((H,O)) and oxygen(O) to form iron oxide(Fe2Og). That is option B.
What is a chemical change?A chemical change is defined as the change that occurs when two substances reacts or combines to form an entirely new product.
The following are the features that shows that a chemical change has taken place. They include:
colour change, precipitate formation, gas formation, smell change, andchange in temperature.When the above signs are seems there is every reason to accept the fact that a chemical change has occurred in the chemical reaction that took place.
From the chosen option, the reactants and product of the chemical reaction are:
Iron (Fe) + water (H2O) --> iron oxide(Fe2Og)
This reaction is a chemical reaction as the product formed leads to a colour change known as rust.
Learn more about chemical change here:
https://brainly.com/question/19794032
#SPJ1
Buffers work best when. Buffers work best when. The ratio of h to oh- is close to 1. 0. Nearly all of the buffer molecules are undissociated. Nearly all of the buffer molecules are dissociated. The ph is nearly neutral. About half of the buffer molecules are dissociated
The corrcet answer is option D: About half of the buffer molecules are dissociated.
Buffers work best when about half of the buffer molecules are dissociated.
In chemistry, an aqueous solution that can resist change in pH when acidic or basic substances are added to it is called a buffer solution.
The main components of a buffer are a weak acid and a conjugate base and vice versa.
When an acid or a base is added to it, it cancels out its effects and makes the solution neutral.
In this way, it maintains a very stable pH of the solution under all conditions.
For a chemical reaction, buffers are really important and handy solutions.
If you need to learn more about buffers click here:
https://brainly.com/question/1385846
#SPJ4
pls help me?
list 5 items that have evolve overtime
(e) A 0.050 mol sample of a hydrocarbon was burned in excess oxygen.
The products were 3.60 g of water and 6.60 g of carbon dioxide.
(i) Calculate the number of moles of carbon dioxide produced.
Relative atomic masses: C = 12; O = 16.
Moles of carbon dioxide =
*
(2)
The correct answer is 0.15.
We are aware that there is 0.05 mol of an unidentified hydrocarbon we will refer to as "X" and that its burning produces 6.6 g of carbon dioxide and 3.6 g of water.
These quantities might be converted to moles by applying the following formula:
amount= mass/ relative atomic mass
Thus, the following equation may be written for H2O: moles = 3.6 / 18 = 0.2 and for CO2: moles = 6.6 / 44 = 0.15.
0.05X + x'O2 = 0.15CO2 + 0.2H2O
This may be made simpler by dividing through by 0.05 (this step is likely to be the most helpful to you), resulting in:
1 x + x O2 = 3 co2 + 4 H2O
The hydrocarbon must have been the source of all the carbon in the carbon dioxide and all the hydrogen in the water.
Accordingly, 4 x 2 = 8 moles of H and 3 x 1 = 3 moles of C.
There are 3/1 = 3 Cs and 8/1 = 8 Hs in one X molecule.
This clearly identifies C3H8 or propane as the hydrocarbon X (dividing by 1 seems unnecessary, but it illustrates the process to use if there were more than one mol of X in the first equation).
To learn more about number of moles of carbon dioxide refer the link:
https://brainly.com/question/12723070
#SPJ9