Answer:
U could use the formula
Explanation:
To calculate the number of atoms in a sample, divide its weight in grams by the amu atomic mass from the periodic table, then multiply the result by Avogadro's number: 6.02 x 10^23
10. What is the mass number, symbol, and
charge of an ion that contains 87 protons,
136 neutrons and 86 electrons?
Explanation:
mass number = sum of protons and neutrons
= 87 + 136
= 223
chemical symbol = Fr
ion charge = +1 (because it has one more proton than electron)
atomic mass number = sum of protons and neutrons
= 87 + 136
= 223
chemical symbol = Fr, ion charge = +1 (because it has one more proton than electron)
What is atomic mass ?Atoms are the basic and smaller units of elements which cannot be broken down further chemically, atoms and elements are organized and represented onto a display called the periodic table.
Atoms are composed of protons, neutrons, and electrons, where protons and neutrons present at the nucleus center of the atom where as electron surrounds the nucleus.
The center of the atom makes up most of the mass of the atom as this is made up of protons and neutrons. Protons are positively charged particle and neutrons have neutral charge, respectively, and each are have a mass of 1 atomic mass unit (amu).
Electrons are negatively charged particle and Amu's are units of measurement for atomic mass, proton and neutron are both equal to 1 amu.
Atomic mass units are based on the masses of protons and neutrons band one carbon atom has only six protons and usually six neutrons in the nucleus.
For more details regarding atomic mass, visit
https://brainly.com/question/17067547
#SPJ2
What is the subscript for Br in 12NaBr?
Answer:
I am not sure you would have to screenshot ur page
How many moles are there in 2.87x10^23 molecules C3H8?
Answer:
0,5 moles
Explanation:
N = L × n
n = N ÷ L
n = 2,87 × 10²³ ÷ 6,02 × 10²³
n = 2,87 ÷ 6,02
n = 0,47 moles or 0,5 moles
. The reaction rates of many spontaneous reactions are actually very slow. Which of these statements is the best explanation for this observation? (1) The activation energy of the reaction is large. (2) AG for the reaction is positive. (3) Such reactions are endothermic. (4) The entropy change is negative.
In reality, spontaneous reactions occur relatively slowly because The reaction's activation energy is high.
Hence, Option 1 is correct.
A spontaneous reaction is one that favors the creation of products in the environment in which it is taking place.Given that spontaneous reactions discharge free energy, the sign of G must be negative. There are four distinct conceivable combinations because both H and S can be either positive or negative depending on the features of the specific reaction.An exothermic example of a spontaneous reaction is a raging campfire (there is a decrease in the energy of the system as energy is released to the surroundings as heat).Find more information about Activation energy here:
brainly.com/question/1380484
#SPJ4
The kind of molecular motion that mostly relates to the temperature of a substance is
A) translational motion.
B) rotational motion.
C) vibrational motion.
D) all about equally
The kind of molecular motion that mostly relates to temperature of a substance is : A) translational motion.
What is meant by translational motion?Motion in which all the points of a moving body moves uniformly in the same direction. If object is undergoing translatory motion, we can see that there is no change in the orientation of object. Translatory motion is also called translational motion.
In kinetic theory of gasses, increasing the temperature of a gas increases the average kinetic energy of the molecules, causing an increased motion. This increased motion increases outward pressure of the gas, which an expected result from the ideal gas equation (PV=NkT).
To know more about translational motion, refer
https://brainly.com/question/1995481
#SPJ4
What volume of 0.145 MNaOH is required to reach the equivalence point in the titration of 45.0 mL of 0.105 M HNO3
The volume of 0.145 M NaOH is required to reach the equivalence point in the titration of 45.0 mL of 0.105 M HNO₃ is 32.58 mL.
Given that :
the molarity of the HNO₃ , M1 = 0.105 M
the volume of the HNO₃ , V1 = 45 mL
the molarity of the NaOH , M2 = 0.145 M
the volume the NaOH , V2 = ?
by using the equation given below , we get:
M1 V1 = M2 V2
0.105 × 45 = 0.145 × V2
V2 = 4.725 / 0.145
V2 = 32.58 mL
Thus volume of the NaOH is 32.58 mL.
To learn more about volume here
https://brainly.com/question/13144728
#SPJ4
Identify the Lewis acid in the following reaction: Pt2+(aq) + 4NH3 (aq) ? Pt(NH3)4,2+(aq)
a) Pt2+
b) NH3
c) Pt(NH3)4,2+
The Lewis acid in the following reaction: Pt2+(aq) + 4NH3 (aq) ?Pt(NH3)4,2+(aq) is : a) Pt2+.
What do you understand by a Lewis acid?Platinum ion (Pt2+) ( P t 2 + ) is a Lewis acid in the given reaction because it accepts pair of electron from ammonia.
A Lewis acid is any substance, such as H+ ion, that can accept a pair of nonbonding electrons. In other words, Lewis acid is an electron-pair acceptor. Lewis acid is chemical species that has an empty orbital which is capable of accepting electron pair from Lewis base to form a Lewis adduct.
To know more about Lewis acid, refer
https://brainly.com/question/12326649
#SPJ4
What happens to the energy put into the ice maker? (What is it used to do? How
is it transformed or transferred?)
Answer:
When ice or any other solid melts, its potential energy increases. Indeed, this is the only increase in energy, since the thermal kinetic energy, or temperature, does not increase while melting. Potential energy is the latent energy that could be released by the water, and this increases because the water will release heat energy if it is frozen solid again.
Ice is the lowest energy state of water at normal Earth pressures. At each phase change of water, whether ice to liquid water or liquid water to water vapor, the potential energy decreases. This is due to the Law of Conservation of Energy. Materials undergoing a change of state absorb or release heat energy, but their temperatures do not change. This is because, while the state change is occurring, all the heat energy is converted into the potential energy of the new state of matter.
Water, in particular, has a very large change in potential energy during phase changes. It takes a great deal of energy to change water from one state to another. This is because of the strong hydrogen bonds that form between water molecules. The liquid phase allows water molecules to be in contact with each other, while the solid phase puts water molecules in an overall optimal configuration relative to each other.
Explanation:
The following reaction shows the products when sulfuric acid and aluminum hydroxide react.
2Al(OH)3 + 3H2SO4 → Al2(SO4)3 + 6H2O
The table shows the calculated amounts of reactants and products when the reaction was conducted in a laboratory.
What is the approximate amount of the leftover reactant?
11. 73 g of sulfuric acid
10. 33 g of sulfuric acid
11. 12 g of aluminum hydroxide
13. 67 g of aluminum hydroxide
The remaining reactant (Aluminum Hydroxide) weighs approximately 11.73 g.
Hence, Option A is correct.
Al(OH)3 has a molar mass of 78 g.H2SO4 has a molar mass of 98 g.Given:Al(OH)3 mass = 30gH2SO4 mass = 35gAl number of moles (OH)3 = 30/78 =0.385H2SO4 mole number = 35/98 = 0.357The provided reaction states that 2Al(OH)3 + 3H2SO4 Al2 (SO4)3 + 6H2OAl, 2 moles (OH)H2SO4 is equal to 3 moles.Al 1 moles (OH)H2SO4 is equal to 3/2 moles.Al 0.385 moles (OH)0.578 moles of H2SO4 are equal to 3 = (3/2) x 0.385 moles of H2SO4.But the amount of H2SO4 is only 0.357 moles.H2SO4 is the limiting reagent as a result.Al(OH)3 is produced when 0.357 moles of H2SO4 react with = 2/3 x 0.357 moles of Al(OH)3.Al(OH)3 leftovers are therefore 0.147 moles (0.385 - 0.238 moles).Al(OH)3 has a molecular weight of 78 g, hence 78 x 0.147 g is one mole.= 11.43 g11.73 g of Al(OH)3 will be left behind as a result.To know more about limiting reagent here
https://brainly.com/question/14222359
#SPJ4
What are the 7 are elements?
The classical elements or seven elements in nature are plants, warm energy, soil, mineral, water, cold energy, and air.
Living organisms incorporate distinctly massive quantities of oxygen, carbon, hydrogen, nitrogen, and sulfur (those 5 factors are called the majority factors), together with sodium, magnesium, potassium, calcium, chlorine, and phosphorus (those six factors are called microminerals). From the smallest atom to a massive whale to the sun machine itself, all matters are stated to be composed of a few aggregate of those elements. Halogens belong to group 17, and they acquire only one electron in order to attain stable electronic configuration.
To learn more about elements check the link below:
https://brainly.com/question/28376204
#SPJ4
state the precaution that must be taken in carrying out an experiment with hydrogen
Answer:
Precautions must be taken to remove all possibilities of fire or explosion.
Explanation:
Since Hydrogen is a very flamable or combustible gas, it is neccesary to avoid smoking, remove sourcs of sparks, flames or heat and hydrogen should be used in a well ventilated area.
Answer:
The generation and use of hydrogen is dangerous. Mixtures of hydrogen and air can be highly explosive. Never smoke near a place where hydrogen is generated or being used. Remove all possible sources of flame and sparks. Hydrogen should only be generated and used in a well ventilated out door area. Precautions must be taken to remove all possibilities of fire or explosion.
The first few bubbles of hydrogen gas should not be collected since they contain air mixed with the gas. Air mixed with hydrogen forms an explosive mixture.
A flame should not be brought near the apparatus since hydrogen is inflammable.
HCl(aq)+NaOH(aq)→NaCl(aq)+H2O(l)
A student had two dilute, colorless solutions, HCl(aq) and NaOH(aq), which were at the same temperature. The student combined the solutions, and the reaction represented above occurred. Which of the following results would be evidence that a chemical reaction took place?
'The temperature of the reaction mixture increases' would be evidence that a chemical reaction took place.
What is a dilute solution?
A dilute solution is a solution that contains fewer solute particles than a more concentrated solution. Dilute solutions are generally less concentrated than more concentrated solutions and are often made by adding more solvent to the solution.
When a chemical reaction takes place, energy is released in the form of heat. This increase in temperature is basically known as an exothermic reaction. An increase in temperature is a sign that a chemical reaction has taken place, as the reaction mixture is absorbing the energy released from the reaction.
To know more about a dilute solution,
https://brainly.com/question/27097060
#SPJ4
Use atomic masses to demonstrate that the balance equation for the formation of iron(III) chloride obeys the law of conservation of mass. Fe + Cl2 → FeCl3
Using the law of the conservation of mass, the reactions can be shown to obey the law.
What is the law of conservation of mass?We need to know what the law of the conservation of mass says so that we can be able to know how we can be able to apply the law in the proper perspective. We have to know that the law says that total mass of the system would remain constant. The implication of this is that the mass before the reaction would be the same as the mass after the reaction. The mass of the substance must be able to add up in the system that is under study as we have one here.
Mass of the iron = 56 g
Mass of the chlorine = 35.5 g
Balanced reaction equation;
[tex]2Fe + 3Cl_{2} ---- > 2FeCl_{3}[/tex]
This is the formation of the iron III chloride
Total mass on the right hand side = 2(56) + 6(35.5) = 325 g
Total mass on the left hand side = 2[56 + 3(35.5)] = 325 g
Learn more about conservation of mass:https://brainly.com/question/13383562
#SPJ1
A saturated solution of Ammonium Chloride is dissolved in 100 g of water.
If the saturated solution is cooled from 50°C to 30°C, how many grams of
precipitate will be formed?
Answer:
10 g
Explanation:
All we need is to read off the solubility curve attached to this answer. The solubility curve is a plot of solubility of a solute against temperature.
By reading off the solubility curve, we can know the mass of precipitate that crystallizes out as the solution is cooled from 50°C to 30°C.
From the solubility curve;
Mass of Ammonium Chloride dissolved at 50°C = 50 g
Mass of Ammonium Chloride dissolve at 30°C = 40 g
Hence;
Mass of precipitate formed = 50 g - 40 g
Mass of precipitate formed = 10 g
A compound is found to contain 43.64 % phosphorus and 56.36 % oxygen by weight The molecular weight for this compound is 283.88 g/mol. What is the molecular formula for this compound
A compound is found to contain 43.64 % phosphorus and 56.36 % oxygen by weight The molecular weight for this compound is 283.88 g/mol. is the molecular formula for this compound is P₂O₅.
Given that :
mass of the oxygen = 56.36 %
molar mass of the oxygen = 16 g /mol
moles of the oxygen= mass / molar mass
= 56.36 / 16
= 3.52 mol
mass of the phosphorus = 43.64 %
molar mass of the phosphorus = 31 g/mol
moles of the phosphorus = 43.64 / 31
= 1.41 mol
dividing by the smallest one :
moles of the phosphorus = 1 = 2
moles of the oxygen = 2.5 = 5
The molecular formula is P₂O₅.
To learn more about molecular formula here
https://brainly.com/question/9529491
#SPJ4
What is natural gas made of? Where does the energy and matter come from?
Answer:
a compound with one carbon atom and four hydrogen atoms (CH4).
Explanation:
Natural gas is a fossil energy source that formed deep beneath the earth's surface. Natural gas contains many different compounds. The largest component of natural gas is methane.
How many ATP does ATP produce?
The bulk of ATP production occurs during cellular respiration within the mitochondrial matrix, producing around thirty-two ATP molecules for every molecule of oxidized glucose.
What is ATP?The energy currency of the cell is ATP (adenosine triphosphate). It is a natural chemical molecule made up of phosphate groups, adenine, and the sugar ribose. These molecules supply energy to the body's many metabolic operations. Therefore, it is dubbed "Energy Currency of the Cell". ATP can be utilized to store energy for future reactions or it can be used to pay for reactions when the cell need energy. Animals use ATP to store the energy received from food breakdown. Similarly, plants use ATP molecules to collect and store the energy they receive from light during photosynthesis.
Here,
The majority of ATP is produced during cellular respiration within the mitochondrial matrix, which produces around thirty-two ATP molecules for every molecule of oxidized glucose.
To know more about ATP,
https://brainly.com/question/14637256
#SPJ4
dental cement, Zn3(PO4)2
Give only the names of the elements alphabetically, separating them with commas.
Zinc, phosphorus and oxygen are elements contained in dental cement (Zn₃(PO₄)).
Dental cements have a wide range of dental and orthodontic applications. Common uses include temporary tooth restoration, lining cavities to protect the pulp, sedation or isolation, and cementation of fixed prosthetic devices.
A cement-retained bridge is simply a dental device that is permanently fixed in the mouth to restore the mouse's function and aesthetics and to prevent many of the consequences of tooth loss that affect the immediate aftermath of losing natural teeth.
Learn more about prosthetic devices visit:
brainly.com/question/30158376
#SPJ4
6.0 mol Al reacts with 4.0 mol O2 to form Al2O3.
4A1+30₂ → 2Al₂O3
How many moles of Al2O3 form when 4.0 mol Al reacts?
2 moles of Al₂O₃ will be produced when 4 moles of Al reacts in accordance with the above equation.
How to calculate moles using stoichiometry?Stoichiometry refers to the study and calculation of quantitative (measurable) relationships of the reactants and products in chemical reactions (chemical equations).
According to this question, 6.0 moles of Al reacts with 4.0 mol of oxygen gas to form Al₂O₃ as follows:
4Al + 30₂ → 2Al₂O₃
Based on the above equation, 4 moles of Al reacts to form 2 moles of aluminium oxide.
This means that 4 moles of aluminium will produce 4 × ²/4 = 2 moles of aluminium oxide.
Therefore, 2 moles of Al₂O₃ will be produced by 4 moles of aluminium.
Learn more about stoichiometry at: https://brainly.com/question/9743981
#SPJ1
Velma and Shaggy are debating on which cleaning solution to use when cleaning the Mystery Machine based on how strong the solution may be.
Velma recommends using a 0.25 M NaOH solution with a pH of 13.40.
Shaggy recommends using a 0.025 M NaOH solution with a pH of 12.50.
Who is recommending the stronger cleaning solution, Velma or Shaggy? Why is their recommendation correct?
Answer:
velma is recommending the stronger soloution
Explanation:
because firstly velmas solution is more concentrated and the pH level of her solution is more Alkaline than shaggies solution
Why the properties of elements are repeated after 2 8 18 and 32 elements?
The properties of the elements are repeated after 2 8 18 and 32 elements because these are the maximum number of the electrons that the four shells contains.
The electronic configuration of the elements in the periodic table are repeated because the maximum number of the electrons that the four shells can have are 2 8 18 and 32. the name of the four shells are K , L, M, N. The electronic configuration of the elements are repeated and due to this the properties of the elements are repeated.
Thus, the properties of the elements are increases because the electronic configuration are repeated in the periodic table.
To learn more about periodic table here
https://brainly.com/question/11155928
#SPJ4
How many geometric isomers are possible for the complex [CrF3Br3]3– ?
To solve this we must be knowing each and every concept related to isomer. Therefore, two geometric isomers are possible for the complex [CrF[tex]_3[/tex]Br[tex]_3[/tex]]₃⁻.
What is isomer?
An isomer is a chemical substance that has the same number and kinds of atoms like another chemical species that differs from it in terms of attributes due to the way the atoms are organized.
Stereoisomerism includes geometric isomerism. It is sometimes referred to as E-Z isomerism or cis-trans isomerism. Geometric isomerism is caused by cyclic compounds' constrained rotation around carbon-carbon double or single bonds. The complex [CrF[tex]_3[/tex]Br[tex]_3[/tex]]₃⁻ has two geometric isomers, one is facial and other is meridional.
Therefore, two geometric isomers are possible for the complex [CrF[tex]_3[/tex]Br[tex]_3[/tex]]₃⁻.
To learn more about isomer, here:
https://brainly.com/question/28188244
#SPJ1
A certain volume of gas at 298kelvin is heated such that its Volume and pressure are now 4 times their original value. what is the new temperature
Answer: The new temperature is 4768 K.
Explanation:
Given: [tex]T_{1}[/tex] = 298 K, [tex]V_{1}[/tex] = V, [tex]P_{1}[/tex] = P
[tex]T_{2}[/tex] = ?, [tex]V_{2}[/tex] = 4V, [tex]P_{2}[/tex] = 4P
Using the combined gas law formula as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}[/tex]
Substitute the values into above formula as follows.
[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\frac{P \times V}{298 K} = \frac{4P \times 4V}{T_{2}}\\T_{2} = 4768 K[/tex]
Thus, we can conclude that the new temperature is 4768 K.
a chloride of rhenium contains 63.6% rhenium. what is the formula of this compound?
A chloride of rhenium contains 63.6% rhenium. the formula of this compound is Re2Cl3.
The chemical trirhenium nonachloride has the formula ReCl3, which is occasionally also written as Re3Cl9. It is a hygroscopic solid that is dark red in color and insoluble in common solvents. The substance is significant in the development of inorganic chemistry since it was the first cluster compound to have metal-metal links. [1] It serves as the raw ingredient for the production of various rhenium complexes. Rhenium is an atomic number 75 chemical element with the symbol Re. It is a heavy, third-row transition metal in group 7 of the periodic table that is silvery-gray in color. Rhenium is one of the rarest elements in the Earth's crust, with an estimated average concentration of 1 part per billion (ppb).
learn more about Rhenium Refer:brainly.com/question/13294446
#SPJ4
Which represents the greatest mass?
• all the same
• 1.0 mol P
• 1.0 mol I
• 1.0 mol K
• 1.0 mol Al
Answer:
it is 1 mole of I is correct
A ample of helium wa compreed at 35 °C from a volume of 0. 5 L to 0. 25 L where the preure i 500 mmHg. What wa the original preure?
The original pressure was 1000 mmHg.
What is pressure?Pressure is a force applied to a surface or object over a given area. Pressure can be generated in a variety of ways, including through mechanical force, electrical force, or through changes in temperature or chemical reactions. Pressure can be measured using a variety of devices, including a barometer, manometer, or gauge. Pressure is an important concept in many fields such as physics, engineering, chemistry, and medicine. It can be used to measure the force of a liquid or gas, the pressure of a liquid or gas, or the pressure at a certain depth in the ocean.
To learn more about pressure
https://brainly.com/question/25736513
#SPJ4
Puffy Chalmers was in his room, admiring his Mr. Drought mask, when his mother, Cookie Chalmers, barged into his room. She was so tired of the mask, she ripped it up and threw the pieces into a metal trash can. Then she pulled a bottle of acid out of her purse, and poured it on the mask pieces causing them to bubble, smoke, and change color. Did she change the mask physically or chemically? Explain your answer using evidence and your knowledge of physical and chemical changes. Help
She changed the mask chemically. Burning of the substance with acid is a chemical change.
A new substance with new qualities is created during burning, which is a chemical alteration that cannot be undone. A chemical change is the transformation of one substance into another, the emergence of new compounds with distinct properties, or any combination of these. It happens when two substances mix to create a new material. Baking soda and vinegar producing carbon dioxide, iron rusting, and wood burning are a few examples of chemical changes. The metabolization of food and the production of amylase from the combining of sugar and saliva are only two examples of the many chemical processes that the body produces.
Learn more about chemical change here:-
https://brainly.com/question/23693316
#SPJ4
Analysis of a 10.150 grams sample of a compound known to contain only phosphorus and oxygen indicates a phosphorus content of 4.433 grams. What is the empirical formula of this compound
A 10.150 grams sample of a compound containing only phosphorus and oxygen which indicates a phosphorus content of 4.433 grams has the empirical formula P₂O₅.
An Empirical formula is defined as the simplest whole number ratio of different atoms present in the molecule of a compound.
given,
mass of the unknown compound= 10.150 g
mass of phosphorus= 4.433 g
therefore, mass of oxygen
=mass of the unknown compound - mass of phosphorus
=10.150-4.433 g
=5.717 g
we know that
molar mass of oxygen = 16 g/mol
molar mass of phosphorus = 31 g/mol
number of moles of oxygen
=mass/molar mass
=5.717g/16gmol⁻¹
=0.357
number of moles of phosphorus
= mass/molar mass
= 4.433g/31gmol⁻¹
=0.143
Now, we will divide the moles by the smallest number of moles (0.143)
O= 0.357 / 0.143 =2.49≈ 2.5
P= 0.143 /0.143 = 1
now, we will multiply both numbers by 2 to get the simplest whole number ratio
O= 2.5×2= 5
P= 1×2= 2
Thus, the empirical formula is P₂O₅.
To know more about empirical formula here
https://brainly.com/question/12239025
#SPJ4
From the information on the table, determine the Mass of
the alloy, Volume of alloy, then the density of the alloy. Be
sure to follow the rules of significant figures in calculations.
Mass of Alloy _____g Bolume of the alloy ______mL. Density of the alloy: ____g/mL.
Answer:
mass of alloy=165.36g
volume of alloy=21.2ml
density of alloy=7.8g/ml
For the same angle of incidence, the angle of refraction in
three different media A, B and C are 10°, 25° and 40°
respectively. In which medium the velocity of light will be
maximum?
Answer:
Media C
Explanation:
We know that ratio of sine of angle of incidence to the sine of refraction gives refractive index. Increases in refractive index increases the range of bending. Here angle of incidence is same in every case. The angle of refraction is greater in c. It has less refractive index and hence, light suffer less bending, which increases its speed.