Answer: yes the atomic number goes on top of the symbol or does the mass number go on top
Explanation: yes the atomic number goes on top of the symbol or does the mass number go on top
after 220 million years, how much of a 100-gram sample of uranium-235 would remain, assuming a half-life of 700 million years?
After 220 million years, The half-life is the time taken for half the mass number of atoms in a sample to decay,700 million years.
What is uranium ?Uranium is a chemical element represented by the symbol U and the atomic number is 92. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons present in it.
Half-Life is the time for a substance U-235 in this case to decay to 1/2 its original mass. Therefore, the problem is asking for the time for U-235 to decay to 1/2 its original mass 100 grams then the decay time is 1 half-life, or 700 million years.
Thus, After 220 million years, The half-life is the time taken for half the mass number of atoms in a sample to decay,700 million years.
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Based on the information given in the passage, which of the following is the standard molar enthalpy of formation for sodium hydroxide?2 NaOCl(aq)+NH3(aq)⇆ NHCl2(aq)+2 NaOH(aq)−470 kJ/mol**According to Hess law, the overall enthalpy change ΔH° of a reaction is equal to the sum of changes in enthalpy of each component.-The signs of the reactants must be changed. Table 1 gives enthalpies of formation, but ammonia and bleach are consumed, not formed. Therefore, they contribute +350 kJ/mol and +45 kJ/mol of enthalpy, respectively.2(350 kJ/mol)+45 kJ/mol+140 kJ/mol+2x=−55 kJ/mol
The standard molar enthalpy of formation for sodium hydroxide is -55 kJ/mol.
The standard molar enthalpy of formation for a substance is the amount of energy required to form one mole of that substance from its component elements in their standard states.
In this case, the reaction given is 2 NaOCl(aq)+NH3(aq)⇆ NHCl2(aq)+2 NaOH(aq) with an overall enthalpy change of -470 kJ/mol. According to Hess's Law, the overall enthalpy change is equal to the sum of the enthalpy changes of each component.
In this case, we need to change the sign of the reactants as they are consumed, not formed, and thus will have a positive value. Therefore, the enthalpies of formation for ammonia and bleach are +350 kJ/mol and +45 kJ/mol respectively.
When adding these values and the enthalpy of formation of NHCl2(aq) which is 140 kJ/mol and using x as the value for the enthalpy of formation of NaOH(aq) we can find that x=-55 kJ/mol.
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Balance the following redox reaction in acidic solution: Cu(s)+NO3−(aq)→Cu2+(aq)+NO2(g) Express your answer as a chemical equation including phases.
The balanced redox reaction in acidic solution is:
Cu(s) + 4H+(aq) + 2NO3-(aq) → Cu2+(aq) + 2NO2(g) + 2H2O(l)
The reaction given is a redox reaction and it needs to be balanced. The reactants and products should have the same number of atoms of each element on both sides of the equation. In the given equation, the number of Copper atoms and Nitrate ions are not balanced on both sides of the equation. In acidic solution, the hydrogen ions (H+) are also present and they also need to be added to the equation. In this case, 4 hydrogen ions and 2 water molecules have been added to the balanced equation to balance the equation.
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Identify substituents on product E q11 A. 2 x -CO2H group and 1 x -SO3H group B. no substituent, only H C. 2 x -SO3H group and 1 x -CO2H group D. 2 x -SO3H group E. 2 x - CH2CH3 group and 1 x -SO3H group
Everything is predicated on benzenation, and the replacement location depends on when benzene is in an electron-rich or electron-deficient position.
Who or what is an electron?A opposite charges new particle known as an electron can either be free or attached to an atom (not bound). Each of the three main types of elements within an element is an electrode that is bonded to it; its other pair are protons plus neutrons.
Where can you find electrons?Electrons are present outside the atom's nucleus, in contrast to protons and neutrons which are contained from the inside of the nucleus at its center. Negative electrons are drawn to the positively charged nucleus because the electric charges of opposite polarity attract one another.
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Enter an equation for the formation of NH3(g) from its elements in their standard states Express your answer as a chemical equation including phases. N2(g) + 3H2(g) +2NH3(g)
The formation of NH3(g) from its elements in their standard states can be represented by the following equation: N2(g) + 3H2(g) --> 2NH3(g).
This equation represents the combination of one molecule of Nitrogen gas (N2) and three molecules of Hydrogen gas (H2) to form two molecules of Ammonia gas (NH3). All the reactants and products are in their gaseous state at standard temperature and pressure.A chemical equation is a written representation of a chemical reaction. It shows the reactants (the starting materials) on the left side of an arrow and the products (the resulting materials) on the right side of the arrow. The arrow represents the transformation of the reactants into products.
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When sodium is heated, a yellow spectral
line whose energy is 3.37 x 10-19 j per photon is
produced
what is the frequency of this light?
explain please
Sodium is heated, a yellow spectral line whose energy is 3.37 x 10-19 j per photon is produced. The frequency of this light is 5.08 x 10^14 Hz
The frequency of light can be calculated using the equation: frequency (ν) = energy (E) / Planck's constant (h).
In this case, the energy of the photon is given as 3.37 x 10^-19 Joules, and Planck's constant is approximately 6.63 x 10^-34 Joules seconds.
So the frequency of this light would be:
ν = E / h
= (3.37 x 10^-19 Joules) / (6.63 x 10^-34 Joules seconds)
= 5.08 x 10^14 Hz
This is a very high frequency, which corresponds to a very short wavelength, in the ultraviolet range of the electromagnetic spectrum.
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you are give a 2.00 g sample of caso4 xh20. given that the mass of anhydrous salt was 1.038 g, find the value of x in the sample.
The molar mass of hydrate part present in the sample of calcium sulfate is 0.962 g.
What is molar mass?Molar mass of a compound or a molecule is defined as the mass of the elements which are present in it.The molar mass is considered to be a bulk quantity not a molecular quantity. It is often an average of the of the masses at many instances.
The molecular mass and formula mass are used as synonym for the molar mass.It does not depend on the amount of substance which is present in the sample.It has units of gram/mole.
Value of mass of water= mass of calcium sulfate-mass of anhydrous form=2.00-1.038=0.962 g.
Thus, The molar mass of hydrate part present in the sample of calcium sulfate is 0.962 g.
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0.50 moles of gas take up 10.5 L
of space under constant pressure
and temperature conditions.
What volume is required to hold
2.0 moles of the gas?
Answer:
Explanation:as V is proportional to n(mole),you can easily calculate using V1/n1=V2/
The volume required to hold 2 moles of the gas is 42 L
Explanation:
(2.0 x 10.5)/0.50
= 21/0.50
= 42 L
what chemical is produced when the protein from food is broken down?
The chemical produced when the protein from food is broken down are amino acids.
Amino acids are defined as the substances that are considered to be the monomers of proteins.Every amino acid has the same structure which consists of a central carbon that is binded to an amino group , carboxyl group and a hydrogen.
Each amino acid also has an another atom or a group of atoms which is bonded to the alpha carbon which are also known as the R group or the variable group of the side chain.There are 20 amino acids that are present in natural proteins and each amino acid has the same backbone.
Proteins are present in food and are made up of amino acids.Thus,amino acids are produced when the protein from food is broken down.
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Explain what is wrong with each of these statements
An aluminium ion looses two electron to form a negative ion.
The formula of carbonate is Co₃⁻².
What is ion ?The term ion is define as any atom or group of atoms that have one or more positive or negative electrical charges. There are two types ion cation and anion.
One lithium atom is react with two fluorine atom to formed lithium fluoride.
Ionic bonds are stronger than covalent bond.
The charge on the barium ion is +2.
When gas turns into liquid its particle get smaller.
Lithium fluoride is a mixture because it contains more than two element.
In an atom the number of electron is equal to the number of proton.
The complete shell contains eight electrons in it.
In the periodic table, elements in the same group does not have the same electron in their outermost shell.
Thus, An aluminium ion looses two electron to form a negative ion.
The formula of carbonate is Co₃⁻².
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write the common and systematic (IUPAC) names of the ether that has the following structure
CH3---O---CH2CH3
Common name: ____
Systematic name: ____
An ether is methoxybutane. Alkoxy alkanes are the term for ethers. The alkoxy group includes the lower alkyl group. There are two alkyl groups in methylbutane. methyl
Is polar ch3coch2ch3?The C-H bonds in CH3CH2CH3 have a relatively modest dipole moment and weak dipole-dipole forces because hydrogen and carbon have very similar electronegativities.
In water, CH3NH3Cl + HCl will entirely dissociate to form 2 mol L-1 ions. Or less 1 mol L-1 of ions will only be partially produced by CH3NH2's reaction with water. written last: CH3NH2.
What is CH3CH2NH2's conjugate base?Sequence of acidity: CH3SH > (CH3)2PH > HCl (strongest acid) (weakest acid). In contrast to the conjugate acid of the amide, the nucleophile of CH3CH2NH2 (ethylamine) does indeed have a single resonance contributor.
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Biannaca Whiteside
Ms. Stephens
Advanced Adult Health
24 February 2022
Case Study 11
J. is a 50-year-old married woman with a genetic autoimmune deficiency; she has had recurrent infective endocarditis. The most recent episodes were a Staphylococcus aureus infection of the mitral valve 16 months ago and a Streptococcus viridans infection of the aortic valve 1 month ago. During the latter hospitalization, an echocardiogram showed moderate aortic stenosis, moderate aortic insufficiency, chronic valvular vegetations, and moderate left atrial enlargement. Two years ago, J. received an 18-month course of total parenteral nutrition (TPN) for malnutrition caused by idiopathic, relentless nausea and vomiting (N/V). She has had coronary artery disease for several years and, 2 years ago had an acute anterior wall myocardial infarction (MI). In addition, she has a history of chronic joint pain. Now, after having been home for only a week, J. has been readmitted to your floor with endocarditis, N/V, and renal failure. Since yesterday, she has been vomiting and retching constantly; she also has had chills, fever, fatigue, joint pain, and headache. As you go through the admission process with her, you note that she wears glasses and has a dental bridge. Intravenous (IV) access is obtained with a double lumen peripherally inserted central catheter (PICC) line. Other orders and your assessment are shown in the box.
Chart View
Admission Orders
STAT blood cultures (aerobic and anaerobic) × 2, 30 minutes apart STAT CMP & CBC Begin PN at 85 mL/hr Piperacillin sodium/tazobactam sodium (Zosyn) 2 g q6h Vancomycin (Vancocin), renal dosing per pharmacy, IVPB q12h Furosemide (Lasix) 80 mg PO daily Amlodipine (Norvasc) 5 mg PO daily Potassium chloride (K-Dur) 40 mEq PO daily Metoprolol (Lopressor) 25 mg PO bid Ondansetron 4 mg IV every 6 hours PRN Transesophageal echocardiogram ASAP
Admission Assessment
Blood pressure 152/48 (supine) and 100/40 (sitting) Pulse rate 116 beats/min
Respiratory rate 22 breaths/min
Temperature 100°F (37°C) Oriented × 3 to person, place and time, but drowsy Grade II/VI holosystolic murmur and a grade III/VI diastolic murmur Lungs clear bilaterally Abdomen soft with slight left upper quadrant tenderness Multiple petechiae on skin of arms, legs, and chest; splinter hemorrhages under the fingernails; hematuria noted in voided urine
1. Which of these statements about IE are true? Select all apply.
a. IE may affect the heart valves. b. IE is an inflammation of the pericardial sac. c. IE is an infection of the innermost layer of the heart. d. Cardiac tamponade is a common complication of IE. e. Heart failure, sepsis, and dysrhythmias may occur with IE
Cardiac tamponade is a common complication of IE, which can affect the heart valves and is an infection of the heart's innermost layer. It is true that heart failure, sepsis, and dysrhythmias can develop with IE.
When blood or fluid accumulates between the heart muscle and the outer covering sac (pericardium), it puts pressure on the heart and causes cardiac tamponade. Cardiac tamponade may happen because of: cutting open an aortic aneurysm (thoracic) terminal lung cancer. chest pain (acute MI). An abnormal or irregular heartbeat is known as a cardiac dysrhythmia (arrhythmia). A dysrhythmia can cause your heart to beat too quickly or too slowly. Another possibility is that your heart's rhythm is disturbed, giving you the impression that a beat has skipped. Your heart may beat excessively rapidly, or too slowly, or with an uneven pattern (tachycardia).
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where in an infrared (ir) specwhich region best matches a typical ir spectrum?trum would you find a strong c
The region around 3,000 to 4,000 cm⁻¹ is the region for most organic compounds, where the C-H stretching vibration is found.
What is organic compounds?Organic compounds are molecules that contain carbon and hydrogen atoms, and sometimes other atoms such as oxygen, nitrogen, sulfur, and phosphorous. Organic compounds are essential for life and are found in a variety of living organisms, including plants and animals. Organic compounds are also found in many non-living objects, such as petroleum and coal. Organic compounds are important because they are used to create energy, medicine, plastics, and many other useful materials. Organic compounds are made up of different combinations of elements, including carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus.
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How could electrical energy be generated by nuclear fission?
Answer:
generates heat to produce steam, which is used by a turbine generator
Explanation:
Draw The Valence Bond Lewis Structure of Ne2^+2. Draw Molecular Orbital Diagram using Shorthand Notation. What is the bond order, number of sigma bonds, number of pi bonds? Is it paramagnetic?
magnetic quality Ne2 particle does not exist because the bond order is zero. Due to the lack of any unpaired electrons, it is diamagnetic. B2 compound.
A valence bond structure: what is it?VB Theory Valance Bond The valence bond hypothesis states that rather than occupying molecular orbitals, electrons in molecules do so in atomic orbitals. A chemical bond is created when two atomic orbitals overlap, and this overlapping causes the electrons to be concentrated in the bond region.
What does a Lewis structure bond look like?Using the model of localized electron bonds Two atoms sharing a pair of electrons results in bonds. Since an orbital may hold two electrons, we typically speak of bonding pairs and lone pairs of electrons.
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Salicylic acid (C7H6O3) reacts with acetic anhydride (C4H6O3) to form acetylsalicylic acid (C9H8O4). 2C7H6O3(aq) C4H6O3(aq) Right arrow. 2C9H8O4(aq) H2O(l) What is the limiting reactant if 70.0 g of C7H6O3 and 80.0 g of C4H6O3 react
We have only 0.5 mol of C₇H₆O₃, so we don't have enough amount of salicylic acid, therefore, salicylic acid acts as limiting reactant.
What are reactants that are limiting?In a chemical reaction, the amount of product that can be formed is limited by the limiting reactant, also known as the limiting reagent, which is the reactant that is consumed first.
It is helpful to convert the masses of reactants into moles in order to comprehend what the limiting reactant is. These are the molecular masses:
C₇H₆O₃ = 138g/mol
C₄H₆O₃ = 100g/mol
Making moles out of masses:
70g C₇H₆O₃ 1mol/138g = 0.5 mol C₇H₆O₃
80g C₄H₆O₃ 1mol/100g = 0.8 mol C₄H₆O₃
In the reaction, 2 moles of C₇H₆O₃ are necessary to react with 1 mol of
C₄H₆O₃ Following this ratio:
0.8 mol C₄H₆O₃ . 2 moles of C₇H₆O₃/ 1 mol of C₄H₆O₃ = 1.6mole C₇H₆O₃
We have only 0.5 mol of C₇H₆O₃ i.e, we don't have enough amount of salicylic acid, therefore, this is the limiting reactant.
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for kw, the product of [h3o+] and [oh-] is_____
The product of [H₃O⁺] and [OH⁻] is calculated as1 × 10⁻¹⁴.
What is Kw?Ionization constant of water, Kw is the product of [H₃O⁺] and [OH⁻].In the autoionization of water, proton is transferred from one water molecule to another to produce hydronium ion (H₃O⁺) and hydroxide ion (OH⁻).
The equilibrium expression for the reaction is Kw = [H₃O⁺][OH⁻], where Kw is the autoionization constant of water.
As, Kw = [H₃O⁺][OH⁻]
In pure water, [H₃O⁺] = [OH⁻] = 1 × 10⁻⁷
So, Kw = [H₃O⁺][OH⁻] = 1 × 10⁻⁷ × 1 × 10⁻⁷
Thus, Kw = [H₃O⁺][OH⁻] = 1 × 10⁻¹⁴
Hence, we get the product of [H₃O⁺] and [OH⁻] is 1 × 10⁻¹⁴.
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at the boiling point, the density of the liquid is 809 g/l and that of the gas is 4.566 g/l. how many liters of liquid nitrogen are produced when 489.0 l of nitrogen gas is liquefied at 77.36 k?
2.758 L Of liquid nitrogen are produced when gas is liquefied.
We are converting gaseous nitrogen to liquid nitrogen. Both of these substances have different densities. Therefore they will occupy different volumes . But they will have the same mass.
Step 1 : Find mass of nitrogen gas
So let us find out the mass of nitrogen gas occupied by 489 L .
The formula for density is, D = Mass / Volume
Density of nitrogen gas 4.566 g/L and the volume occupied by it is 489 L.
Let us plug in these values to find the mass of nitrogen gas.
The equation can be modified as follows.
Mass = Density × Volume
Mass = 4.566 / L × 489
Mass = 2232g
The mass of nitrogen gas is 2232 g.
Step 2 : Find the volume of a liquid nitrogen using the mass
The mass of a liquefied nitrogen is also the same.
Whereas, the density of liquid nitrogen is 809 g/L
Let us plug in this value of mass to find the volume of the liquid.
Volume = 2232 / 809g / L
Volume = 2.758 L
The volume of liquid nitrogen is 2.758 L
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3 ba(clo3)2 + 1 al2(so4)3 - 3 basoa + 2 al(clo3)3
what is the percent yield of a reaction that was expected to yield 45.8 grams of baso, and
yielded 38.4 grams of baso?
The percent yield of reaction is calculated as 83.67%, which implies that 83.67% of expected amount of Baso was actually produced.
What is percent yield of a reaction?The actual yield divided by theoretical yield times 100 is percent yield.
Theoretical yield of Baso will be calculated as :
As, we know, molar mass of Baso = 234.17 g/mol
So, now moles of Baso is (45.8 g Baso) / (234.17 g/mol) = 0.196 mol Baso
Actual yield of Baso will be:
As we know, molar mass of Baso = 234.17 g/mol
So, now moles of Baso is (38.4 g Baso) / (234.17 g/mol) = 0.164 mol Baso
As we know, Percent yield is (Actual yield/Theoretical yield) x 100
= (0.164 / 0.196 ) x 100
So, the Percent yield is 83.67%
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What is the largest difference in electronegativity between two atoms that form a covalent bond?
a. o
ob. 0.4
c. 1.7
od. 2.6
Depending on the difference in electronegativity between the participating atoms, covalent bonds can either be polar or nonpolar.
The correct option C
What makes electronegativity important?The electronegativity of an atom describes its propensity to attract protons or electron density in that direction. It regulates the shared electron distribution between a number of atoms in a bond. The stronger the attraction of the electrons in an atom's bonds, the more electronegativity it possesses.
What are electronegative substances?The strength with which an element draws the shared electrons depends on the value of its electronegativity.
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find the number of grams of co2 that exert a pressure of 785 torr at a volume of 32.5 l and a temperature of 32 celsius
the equation for a ideal gas. PV = nRT, n=PVRT, n=1.34 mol, n=785 torr, 32.5 L62.36 L torr, and (32 + 273) K.
Explain what an ideal gas is.
The definition of an ideal gas is a gas in which the volume of the molecules and the forces between the molecules are so minimal as to not affect the behavior of the gas.
What is an example of ideal gas?
Many gases, including nitrogen, oxygen, hydrogen, noble gases, some heavier gases like carbon dioxide, and mixtures like air, can be classified as ideal gases if certain parameters are kept within reasonable limits over a wide range of temperatures and pressures.
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A nonvesicular rock is made entirely of green 2-millimeter-diameter crystals that have a hardness of 6.5 and show fracture, but not cleavage. The rock is most likely
answer choices
Peridotite
Dunite
Scoria
Granite
Peridotite is the most likely answer.
What is peridotite?Peridotite is a type of igneous rock composed primarily of the minerals olivine and pyroxene. It is the most common rock in the upper mantle of the Earth, and is usually found in regions known as subduction zones where tectonic plates are colliding. Peridotite is formed from the partial melting of mantle rocks, and contains high amounts of magnesium and iron. This type of rock is often mined for gemstones, as well as for its use in construction and jewelry-making.
Peridotite is a type of ultramafic rock made of olivine, pyroxene, and amphibole minerals. It is composed mostly of minerals with a hardness of 6.5 and has a greenish hue, making it consistent with the description given. Furthermore, peridotite is known to fracture, but not cleave, making it the most likely answer given the characteristics of the rock.
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calculate the molar mass of tetraphosphorus decaoxide, p4o10, a corrosive substance which can be used as a drying agent.
As a result, the molecular mass of P₄O₁₀, or tetraphosphorus decaoxide, is 284 g/mol.
What is molecular mass?The molecular mass is the mass of all the atoms present in the molecule. The molecular mass of the compound is calculated using the steps:
Determine the atomic number of each element in the compound.
Each element's atomic mass is multiplied by the number of atoms in that element in the compound.
The mass of all the atoms are added up.
Here,
The given compound is:
P₄O₁₀
The atomic mass of P=31 u
The atomic mass of O=16 u
The molecular mass of P₄O₁₀,
=31*4+16*10
=124+160
=284 g/mol
Hence, the molecular mass of P₄O₁₀ that is tetra phosphorus decaoxide is 284 g/mol .
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PLEASE HELP!!
Show the units in the equation:
△G°=-nFE°
are consistent.
Answer:
Explanation:
In this equation, ΔG° stands for the standard Gibbs free energy of a reaction, n is the number of moles of electrons that are transferred in the reaction, F stands for the Faraday constant (96,485.3 Coulombs/mole), and E° is the standard electrochemical potential. All of these units are consistent, since ΔG° is in Joules, n is in moles, F is in Coulombs/mole, and E° is in volts.
what is the effect on the concentrations of no2-, hno2, and oh- when hno2 is added to a solution of kno2 in water.
When HNO2 is added, concentration of HNO2 rises and the equilibrium is shifted to the left, where it favours NO2 ions and depletes OH ions.
What is the most accurate way to define equilibrium?It is a static or dynamic state of equilibrium between two opposing forces or actions. The extent of a reaction, or the level of the vanishing of the reactants, can be predicted using the equilibrium constant (Kc). A general sense of the relative amounts of the reactants and products can be obtained from the equilibrium constant's magnitude.
The equilibrium's equation is:
NO2- (aq.) + H2O (l) ⇌ HNO2 (aq.) + OH− (aq.)
Le Chatelier's Principle will be applied to ascertain how the addition of the specified chemicals would affect the equilibrium mixture.
The equilibrium is shifted to the left by the addition of HNO2, which raises the concentration of HNO2.
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(6) There are only two elements named after women. Who are the two women? What are the names and the atomic numbers of the elements named after them? What was each woman's contribution to science?
Curium (Cm) and Rhenium are the two elements with female names (Re).
How were the two elements named after women?After Marie Curie, a pioneering researcher in the realm of radioactivity, the element curium, with atomic number 96, was named. She was the first person to receive two Nobel Prizes, one each in physics and chemistry, and her work on the discovery of radium and polonium contributed to the advancement of X-ray technology and the development of cancer therapies.
Rhenium, an element with the atomic number 75, was given its name in honour of Ida Tacke-Rhenium, a German scientist who made the discovery of the substance alongside her husband in 1925. The element was found and isolated by her, and it has since been widely employed in high-temperature alloys, catalysts, and electronic parts.
What was each women's contribution to science?Both of these women made significant contributions to science, and the naming of these elements pays tribute to them. They were pioneers in a male-dominated industry, and their contributions have had a lasting influence on science and technology.
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What would be the advantages of using Al(OH)3 as an antacid rather than NaHCO3, which undergoes the following reaction with stomach acid?
NaHCO3(aq) + HCl(aq) →→→→ NaCl(aq) +
H₂O(l) + CO₂(g)
Answer:
Aluminum hydroxide (Al(OH)3) has several advantages over sodium bicarbonate (NaHCO3) as an antacid. One advantage is that Al(OH)3 does not neutralize stomach acid as quickly as NaHCO3 does, so it can provide longer-lasting relief for symptoms of heartburn and indigestion. Additionally, Al(OH)3 is less likely to cause side effects such as diarrhea, which can be a common problem with overuse of NaHCO3. Furthermore, Al(OH)3 can also adsorb excess stomach acid and form a physical barrier that helps to protect the stomach lining.
What would be the number of phosphorus atoms in a 2.34 g sample of calcium phosphate?
(My answer was 9.1*10^21 but I'm not sure if I went wrong somewhere in the process)
Answer: You were right I'm not sure why it says you're incorrect?
Explanation:
The number of phosphorus atoms in a 2.34 g sample of calcium phosphate is calculated via molar mass and Avogadro's number. Your estimate of 9.1 x 10^21 phosphorus atoms is very close to the actual atoms present.
Explanation:To solve this inquiry, let's start by finding the molar mass of calcium phosphate (Ca3(PO4)2). The molar mass is calculated as follows: 3(40.08 g/mole for Ca) + 2(1.01 g/mole for H) + 2(15.999 g/mole for O) + 2(30.974 g/mole for P) = 310.18 g/mole.
Next, divide the mass of the sample by the molar mass of calcium phosphate to find number of moles: 2.34 g ÷ 310.18 g/mole = 0.00754 moles.
Remember that 1 mole of calcium phosphate contains 2 moles of phosphorus atoms. Therefore, the number of moles of phosphorus atoms is 2*0.00754 = 0.01508 moles.
Then, use Avogadro's number (6.02 x 1023 atoms/mole) to find the number of phosphorus atoms: 0.01508 moles * 6.02 x 1023 atoms/mole = 9.08 x 1021 atoms. Your estimate of 9.1 x 1021 phosphorus atoms is essentially correct!
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Give the chemical symbol for the element with the following ground state electron configuration. [Ar]4s^2 3d^2
The chemical symbol for the element Ti for the given ground state electron configuration. [Ar]4s² 3d²
How do you determine the configuration of an electron?Electron arrangements around an atom's nucleus are known as electron configurations. As an illustration, lithium's electron configuration, 1s²2s₁, indicates that the metal has two electrons in the 1s subshell and one electron in the 2s subshell.
The shell number (n) is the first symbol used to represent an electron configuration, followed by the type of orbital and the superscript number of electrons in the orbital. Consider this: The periodic table shows that oxygen has eight electrons.
chemical symbol: Ti
name: titanium
4s²:
n = 4
l = 0
ml= 0
3d²:
n = 3
l = 2
ml= -2,-1,0,+1,+2
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Find pH in the following solution if their [H^+] concentration is : a) [5x10^-9 ml/dm^3]
Answer:
pH= 8.30
Explanation:
The pH of the solution with a [H+] concentration of 5x10-9 ml/dm^3 is 8.30. This can be calculated using the pH to H⁺ formula: pH=−log([H+]). Substituting the given [H+] concentration, we get: pH = −log(5x10-9) = 8.30.
