This statement about density is True.
The mass of a material substance per unit volume is known as density. The equation for density is d = M/V, where d represents density, M is mass, and V is volume. Density is often measured in grams per cubic centimeter. For instance, water has a density of 1 gramme per cubic centimeter, compared to Earth's density of 5.51 grammes.
The kilograms per cubic metre unit is another way to express density (in metre-kilogram-second or SI units). For instance, the weight of air per cubic meter is 1.2 pounds. The densities of typical solids, liquids, and gases are listed in textbooks and manuals. Through density, it is simple to calculate a body's mass from its volume or vice versa.
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A water sample of unknown phosphate concentration is found to have an absorbance of 0.460 after treatment with tin(II) chloride and ammonium molybdate. What is the concentration of phosphate ion in the sample?
Answer:
07 Question (2 points) See page 160 The concentration of phosphate ions in water samples can be determined by spectrophotometry. Samples are treated with tin(II) chloride and ammonium molybdate to react with the phosphate to make a blue complex. Before testing an unknown sample, a series of solutions with known concentrations is tested to create a calibration plot. Calibration data with concentration units of part per million (ppm) are shown in the graph below. Calibration Data for Phosphate Analysis D Absorbance 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 04 Rat B 0.0434 -0.0264 R = 0.9945 A A water sample of unknown phosphate concentration is found to have an absorbance of 0.460 after treatment with tin(II) chloride and ammonium molybdate. What is the concentration of phosphate ion in the sample? ppm
Write the equilibrium constant expression for this reaction:
NH+4(aq) → NH3(aq)+H+(aq)
The equilibrium constant expression for the given reaction is:-
Equilibrium constant = [NH₃] [H⁺] / [NH₄⁺]
An equilibrium constant is the ratio of the concentration of products to the concentration of the reactant raised to the power of its coefficients.
The rate constants are constant at some particular temperature. It is equal to the rate constant for the forward reaction divided by the rate constant for the backward reaction.
aA + bB ⇄ cC + dD
The equilibrium constant for the reaction is given as
NH₄⁺ (aq) → NH₃ (aq) + H⁺ (aq)
The expression is given as
Equilibrium constant = [NH₃] [H⁺] / [NH₄⁺]
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Is hydrogen explosive? if so what makes it explosive?
please explaen.
50 points
Answer:
Hydrogen(H) is in fact explosive. So H and Oxygen have a strong bond which means when they have some sort of contact it will cause a reaction. H consists of one proton and one electron which means that this simple structure can cause a chemical reaction that could cause something to be flammable and easy to ignite, it happens when H comes in contact with the oxygen in the air it can cause some sort of explosion or something relatively similar. I hope this makes sense.
Explanation:
Hope this helps:).........if not then sorry for wasting your time and may God bless you<3
The plasma level of a drug was found to be 5ng/dL.
How many milligrams of drug are present in 1 L of plasma?
please careful about the significant point and decimal place/point
The mass in milligrams of the drug present in 1 L of plasma is 5 * 10⁻⁵ mg
What is plasma?Plasma is the liquid part of blood which contains dissolved solutes such as ions, proteins and sugar.
Plasma concentration of fluid are important in general health, diagnosis and treatment of diseases.
The plasma level of the drug was found to be 5ng/dL.
I dl = 1/10 L
1 dL = 0.1 L
1 ng = 1 * 10⁻⁶ mg
5 ng = 5 * 10⁻⁶ mg
The milligrams of drug are present in 1 L of plasma = 5 * 10⁻⁶ mg/0/ L
The milligrams of drug are present in 1 L of plasma = 5 * 10⁻⁵ mg
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PLEASE HELP ASAP
Which element is a nonmetal?
O Hg
O Cu
O He
O Re
Answer:
He
Explanation:
Helium is a gas, not a metal.
Describe the climate of Lake Tahoe. How does its elevation and closeness to the ocean affect the climate?
The climate of a region is influenced by large bodies of water like oceans, seas, and major lakes. As a result, coastal regions will have different summer and winter temperatures.
What type of climate is there in Lake Tahoe?The weather in Tahoe is dry and moderate. There is relatively little humidity even in the summer, and snowstorms in the winter are when most precipitation occurs. The lake lies 1,890 meters above sea level at an elevation of 6,200 feet, although the nearby mountain peaks are between 9,000 and 10,000 feet higher (2,743 to 3,048 meters.)
What is the purpose of Lake Tahoe?In Nevada, Lake Tahoe is used as a reservoir for municipal and irrigation water storage. About 75% of the water supply for the quickly expanding Reno-Sparks region comes from Lake Tahoe and a few smaller publicly and privately owned reservoirs in the Truckee River system.
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What occurs when the air cools and begins to sink
Once hot air cools, it sinks to the earth's surface, here it is warmed by the ocean before rising back. This is known as a convection current.
Why convection current occurs?Differential heating usually creates convection currents. Warmer (less dense) material rises, and cooler (more dense) material sinks.
The above movement is responsible for the formation of circulation patterns known as convection currents in the Earth's atmosphere, water, and mantle.
Convection currents in the Earth's mantle are thought to be the driving force behind tectonic plate movement.
Thus, convection current occurs when the air cools and begins to sink.
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What sets of ions are present in calcium hydrogen phosphate, CaHPO4?
The "di" prefix in the common name comes from the removal of two protons from phosphoric acid, [tex]H_3PO_4[/tex], during the formation of the [tex]HPO_4^2^-[/tex]anion. Calcium mono-hydrogen phosphate is another name for dibasic calcium phosphate.
What is an ion?An ion is basically an electrically charged atom or molecule. By convention, the charge of an electron is considered to be negative, and this charge is equal to and opposite to the charge of a proton, which is considered to be positive.
The common name's "di" prefix originates from the expulsion of two protons from phosphoric acid, [tex]H_3PO_4[/tex], even during establishment of the [tex]HPO_4^2^-[/tex] anion.
Thus, it can be concluded that the ions in the calcium hydrogen phosphate are calcium ion and hydrogen phosphate ion.
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* Please Help!!!!!
A sample of carbon monoxide occupies 7.48 L at 298.0 K and 726 torr. Find its volume at −23°C and 444 torr.
The new volume occupied by the carbon monoxide at the given pressure and temperature is approximately 10.27 Liters.
What volume does the carbon monoxide occupies?Combined gas law put together both Boyle's Law, Charles's Law, and Gay-Lussac's Law. It states that "the ratio of the product of volume and pressure and the absolute temperature of a gas is equal to a constant.
It is expressed as;
P₁V₁/T₁ = P₂V₂/T₂
Given the data in the question;
Initial volume V₁ = 7.48LInitial pressure P₁ = 726 torr = ( 726/760 )atmInitial temperature T₁ = 298.0 KFinal pressure P₂ = 444 torr = ( 444/760 )atmFinal temperature T₂ = −23°C = ( −23 + 273.15 )K = 250.15KFinal volume V₂ = ?Plug the given values into the above formula and solve for the final volume.
P₁V₁/T₁ = P₂V₂/T₂
P₁V₁T₂ = P₂V₂T₁
V₂ = P₁V₁T₂ / P₂T₁
V₂ = ( (726/760) × 7.48 × 250.15 ) / ( (444/760) × 298.0 )
V₂ = 1787.4139 / 174.0947
V₂ = 10.27 L
The new volume occupied by the carbon monoxide at the given pressure and temperature is approximately 10.27 Liters.
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What scientific steps would you take to identify if something is or isn’t matter?
How many square centimeters are in an area of 3.90 inch² ?
Express your answer numerically in square centimeters.
Answer:
3.90 Square Inch = 25.16124 Square Centimeter
Explanation:
How to convert Square Inch to Square Centimeter ? 1 square inch (in²) is equal to 6.4516 square centimeter (cm²).
8. Does hydrogen have more electrons than lithium?
Answer:
Lithium has more electrons than Hydrogen
Explanation:
Lithium has 2,1 electrons
Hydrogen has 1 electrons
If 70 moles of CH4 reacted with excess O2, how many grams of H2O are formed? CH4 (g) + 2 O2 (g) -------> CO2 (g) + 2 H2O (g)
The mass (in grams) of H₂O produced from the reaction is 2520 grams
How to determine the mass of H₂O producedWe'll begin by writing the balance equation for the reaction. This is given below:
CH₄(g) + 2O₂(g) -------> CO₂(g) + 2H₂O(g)
From the balanced equation above,
1 mole of CH₄ reacted to produce 2 moles of H₂O
Therefore,
70 moles of CH₄ will react to produce = 70 × 2 = 140 moles of H₂O
Finally, we shall determine the mass of water, H₂O produced from the reaction as follow:
Mole of water, H₂O = 140 molesMolar mass of water, H₂O = 18 g/molMass of water, H₂O =?Mole = mass / molar mass
Cross multiply
Mass = mole × molar mass
Mass of water, H₂O = 140 × 18
Mass of water, H₂O = 2520 grams
Thus, 2520 grams of water, H₂O were obtained from the reaction
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Your weather app reports the actual temperature as 34°F but the temperature on the thermometer outside is 35°F. What is the percent error of the recorded temperature (absolute error = ±1°F).
The percentage error of the recorded temperature is 2.9%
Formula for percentage errorPercentage error = (absolute error / actual measurement) × 100
Data obtained from the questionThe following data were obtaned from the question:
Actual temperature reading = 34 °FThermometer reading = 35 °FAbsolute error = 1 °FPercentrage error =?How to determine the percentage errorThe percentage error of the recorded temperature can be obtained as follow:
Percentage error = (absolute error / actual measurement) × 100
Percentage error = (1 / 34) × 100
Percentage error = 2.9%
Thus, the perecentage error of the recorded temperature is 2.9%
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How much Tween 20 is needed to prepare 350 mL of a 25% Tween 20 (v/v) solution?
a. 0.875 ml
b. 875 ml
c. 8.75 ml
d. 87.5 ml
87.5 ml of Tween 20 is needed to prepare a 350 mL of a 25% Tween 20 (also called polysorbate 20) (v/v) solution in water via chemical lab methods.
What is Tween 20?By ethoxylating of Sorbian monolaurate in labs or in factories, a compound is formed that is a is a nonionic surfactant of the polysorbate type and is named as Polysorbate 20 or as we commonly call it as Tween 20.
Its other common commercial brand names can be stated as Kolliphor PS 20, Scattics, Alkest TW 20, Tween 20, and Kotilen-20 etc.
Uses of Tween 20It can be employed as a detergent and emulsifier in a variety of home, academic, and pharmaceutical applications due to its stability and relative nontoxicity.
This Tween 20 is also used as a wetting agent in a wide range of flavored mouth drops and thus provides a spreading effect to the other ingredients present in it.
To prepare 350ml 25% Tween 20 v/v solution
25% is the volume of Tween 20 in the entire solution
Thus volume = 25% of 350
= 350 x (25/100)
= 87.5 ml
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a mole of LiF(s) contains 2 moles of ions
1 mole of LiF has 2 moles of ions. Therefore, the given statement is true.
1 mole of LiF (s) contains 1 mole of [tex]Li^+[/tex] ion and 1 mole of [tex]F^-[/tex] ion.
So, total 2 moles of ions are present.
One fluorine (F) atom and one lithium (Li) atom can interact to produce the chemical compound Lithium Fluoride, or LiF.
LiF is an inorganic substance. It is a colorless solid that becomes white as the size of the crystals decreases. Lithium fluoride doesn't have an odor, but it tastes salty and unpleasant. Although it has a structure similar to sodium chloride, it is substantially less soluble in water. This is mostly due to LiF's stronger ionic nature. The ratio of lattice energy to hydration energy determines a compound's solubility in water.
Thus, the statement is true.
The complete question is:
A mole of LiF(s) contains 2 moles of ions. State whether the statement is true or false.
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Perform the calculation and record the answer with the correct number of significant figures. Perform the calculation and record the answer with the correct number of significant figures.
(6.5−6.35)/3.49=
The value of the following expression is 0.0429 rounded off to 0.043. The correct number of significant figures is 2.
The given expression (6.5 - 6.35) / 3.49 is calculated as below
(6.5 - 6.35) / 3.49
0.15 / 3.49
0.04297
0.043
Zeros to the left of the first non-zero digit are considered as not significant. For example 0.00765 has only 3 significant numbers.
When multiplying and dividing measured quantities, the output of the calculation should have the same number of significant figures as the measured quantity with the fewest significant figures. When performing multiple stage calculations, do not round intermediate stage calculation results; keep as many digits as is practical and round off only in the final output
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If the concentration of red dye #40 in the original syrup is 4.68 x 10^-3 M, what is the concentration in dilution #3 written in scientific notation
The final concentration of the solution is 2.75 * 10^-3 M.
What is dilution?We know that the stock solution is the solution from which we are able to prepare other solutions. The concertation of the stock solution is always seen to be higher than the concentrations of the other solutions that are obtained from it.
Given the dilution formula;
C1V1 = C2V2
C1 = initial concentration
C2 - final concentration
V1 - initial volume
V2 - final volume
Thus we have;
4.68 x 10^-3 M * 250 mL = C2 * 425 mL
C2 = 4.68 x 10^-3 M * 250 mL/425 mL
C2 = 2.75 * 10^-3 M
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Missing parts;
A cough syrup contains red dye #40, with a concentration of 4.68 x 10-3 M.a.If you dilute the cough syrup by adding 175 mL of water to a 250. mL sample of the cough syrup, what will be the final concentration?
A reaction, carried out in a bomb calorimeter with Ccal = 5.01 kJ/oC, gives off 318 kJ of heat. The initial temperature of the water is 24.8oC. The final temperature of the water in the calorimeter is ____ oC.
A reaction which is carried out in a bomb calorimeter with Ccal = 5.01 kJ/°C, gives off 318 kJ of heat. The final temperature of the water in the calorimeter is 88.27°C
What is Bomb Calorimeter?The calorimeter which used in order to determine the energy change during the reaction precisely is known as a bomb calorimeter.In modern Bomb calorimeter there is a development of the original type calorimeter known as Berthelot.The modern bomb calorimeter is generally made up of corrosion free steel in which the reaction takes place.The bomb calorimeter is a type of instrument which certainly used to measure the heat of reaction of compound at a fixed volume.It is also used to measure heat which is also called the change of internal energy (denoted by symbol ΔE). In chemistry, the changes of heat of a reaction is measured when there is fixed pressure and volume.Now,
according to the given question,
The given data is :
Ccal = 5.01 kJ/°C
Heat (q) = 318 kJ
Initial temperature = 24.8°C
Final temperature = ?
Now we know that equation of bomb Calorimeter is given by;
Equation:q = cΔT
Hence,
318kJ = 5.01 kJ/°C ( T(final) - 24.8°C )
T(final) = 88.27°C
Thus, from the above conclusion we can say that a reaction which is carried out in a bomb calorimeter with Ccal = 5.01 kJ/°C, gives off 318 kJ of heat. The final temperature of the water in the calorimeter is 88.27°C.
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An atom with 15 protons and 16 neutrons is an atom of
A sulfur, S
B) phosphorus, P
C) gallium, Ga
(D) scandium, Sc
Question 3
What is the maximum number of electrons in the
An atom with 15 protons and 16 neutrons is an atom of phosphorus, P. A neutral phosphorus atom has 15 electrons which is equal to number of proton.
Phosphorus :A mineral called phosphorus is found in many foods naturally and can also be taken as a supplement. It has numbers of function in the body. It is a crucial component of cell membranes, bones, and teeth. It maintains a normal range of blood pH and aids in the activation of enzymes.
What does phosphorus do for the human body?All tissues and cells require phosphorus for their growth, upkeep, and repair, as well as for the synthesis of DNA and RNA, the genetic building blocks. Additionally, other vitamins and minerals like vitamin D, iodine, magnesium, and zinc need phosphorus to be balanced and used.
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What are produced when asteroids, meteoroids, or comets hit the moon's surface?
Craters are produced when asteroids, meteoroids, or comets hit the moon's surface.
What are Craters?This refers to a type of depression which is formed on the surface of the planet, moon etc which are present in the solar system due to hyper velocity impact of a smaller body such as asteroids, meteoroids etc.
Craters can also be formed as a result of the explosion which results from the impact of the smaller bodies mentioned above. The moon has a lot of craters which was formed billions of years ago and is therefore the most appropriate choice in this scenario.
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Your weather app reports the actual temperature as 34°F but the temperature on the thermometer outside is 35°F. What is the percent error of the recorded temperature (absolute error = ±1°F)
The percentage error of the recorded temperature is 2.9%
Formula for percentage errorPercentage error = (absolute error / actual measurement) × 100
Data obtained from the questionThe following data were obtaned from the question:
Actual temperature reading = 34 °FThermometer reading = 35 °FAbsolute error = 1 °FPercentrage error =?How to determine the percentage errorThe percentage error of the recorded temperature can be obtained as follow:
Percentage error = (absolute error / actual measurement) × 100
Percentage error = (1 / 34) × 100
Percentage error = 2.9%
Thus, the perecentage error of the recorded temperature is 2.9%
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Lab: Plate Boundaries and Movement lab report
Answer:
facts yo
Explanation
7. matter of only one type of atom. what's the answer for this crossword puzzle I really need help I've been stuck on this question for 32 minutes !! :(
A substance containing only one type of atom is called a chemical element. This differs slightly from an element, which is a category of atoms based on their number of protons. A chemical element is a substance that exists in the real world and is formed from only one type of atom.
This substance can be a set of atoms present on their very own or the atoms can be bonded together to shape molecules of the simplest type of atom, together with oxygen. while a substance incorporates only one form of an atom, it is known as a detail. each detail has a unique name and specific houses which are one of a kind from all of the relaxation of the elements.
An atom is a particle of count that uniquely defines a chemical detail. An atom consists of a principal nucleus which is surrounded by using one or extra negatively charged electrons. The nucleus is definitely charged and consists of one or more fairly heavy particles known as protons and neutrons. isotopes are members of a family of detail that all have the same wide variety of protons but unique numbers of neutrons.
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A student isolates 1.685 grams of iron (II) oxalate, FeC2O4. What is this amount in moles?
The amount in moles of iron (II) oxalate that has a mass of 1.685 grams is 0.01170mol.
How to convert mass to moles?The number of moles in a substance can be calculated by dividing the mass of the substance by the molar mass.
According to this question, a student isolates 1.685 grams of iron (II) oxalate (FeC₂O₄).
Molar mass of FeC₂O₄ = 56 + 12(2) + 16(4) = 144g/mol
no of moles = 1.685g ÷ 144g/mol = 0.01170mol
Therefore, the amount in moles of iron (II) oxalate that has a mass of 1.685 grams is 0.01170mol.
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A sample of CH4 weighs 3.423 g. How many molecules of CH4 are in the sample writing in scientific notation?
Answer:
1.285 x 10²³ molecules CH₄
Explanation:
To find the amount of molecules in the sample, you need to (1) convert grams to moles (using the molar mass of CH₄) and then (2) convert moles to molecules (using Avogadro's Number). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units (the desired unit should be in the numerator). The final answer should have 4 sig figs like the given value (3.423 = 4 sig figs).
Atomic Mass (C): 12.011 g/mol
Atomic Mass (H): 1.008 g/mol
Molar Mass (CH₄): 12.011 g/mol + 4(1.008 g/mol)
Molar Mass (CH₄): 16.043 g/mol
Avogadro's Number:
6.022 x 10²³ molecules = 1 mole
3.423 g CH₄ 1 mole 6.022 x 10²³ molecules
----------------------- x ------------------- x ------------------------------------------- =
16.043 g 1 mole
= 1.285 x 10²³ molecules CH₄
9.
Which of the following contains one mole of neutrons?
A 1g of H
B 1g of C
C 2g of Mg
D 2g of Ne
Among the following option c "2g of Mg" is correct answer. 2g of Mg contains one mole of neutrons.
What is neutron?
The neutron is a neutral subatomic particle that, with the exception of common hydrogen, is a component of every atomic nucleus. Its rest mass is 1.67492749804 1027 kg, which is slightly more than that of the proton but 1,838.68 times higher than that of the electron. It has no electric charge.
Since you are taking the mass of magnesium (2 g) and dividing by the molecular mass of magnesium (24 g/mol), the formula
[tex]amount of substance=\frac{mass}{molar mass}[/tex]
informs you that you have 1/12 moles of magnesium. The quantity of magnesium in the question is not, however, being asked.
Each magnesium atom contains 12 neutrons (24 - 12). As a result, 1/12 moles of magnesium contain 1 mole of neutrons (1/12)(12).
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Arrange these ions according to ionic radius
Largest to smallest
As3-
Rb+
Sr2+
Se2-
Br-
Largest to smallest ionic radius
As3- > Se2- > Br- > Rb+ > Sr2+ ( ionic radius)
ionic radius is the distance between nucleus of an ion and the point up to which the nucleus has influence on its cloud. measured in nm pm or angstromstrend for ionic radius is the moving down ionic radius increases. left to right, the ionic radius of cations anions and atoms forming ionic bonds decreaseselectron affinity is the specific measure of the energy released when an electron is added to an atom. along the period- increases left to right and along group- decreases down, as lectron affinity increases radius decreaseselectronegativity is quantitive measure of the electron attracting ability in a molecule , along a period- electronegativity increases across and along group - decreases down, as electronegativity inreases radius decreasesTo know more about ionic radius visit :
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at 298 K and 1 atm, which gas has the highest density?
SO3 gas has the highest density.
A modified version of the ideal gas law is used to calculate density, replacing moles and volume with density and molar mass.
The relationship between a gas's density and molecular weight can be demonstrated using the ideal gas law equation. The formula is d = MP/RT, where d is the gas's density in kilograms per liter, M is its molar mass in grams per mole, P is its pressure in atmospheric pressure units, and R is the gas law constant. The equation demonstrates that the molar mass increases as gas density increases.
d = PM/RT
d ∝ M
CO = 28
CO2 = 44
SO3 = 80
Cl2 = 71
Thus SO3 will be more dense.
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Determine the number of atoms in 27.0 grams of calcium, Ca. (The mass of one mole of calcium is 40.08 g.)
You are given the mass of calcium and you are trying to determine the number of atoms. You do not have anything that converts directly from mass to atoms. But what you can do Is use the molar mass to convert two moles. And then use avocado dress number to convert to atoms. So that's the plan that you are going to follow. So you need to start with the massive calcium that we you are given. Which is 61.0 g of calcium. So the first step is to use the molar mass of calcium to convert two moles. You are given the Molar Mass. You told that one mole of calcium Is 40.08 g. If you were not given this information, you could find it on the periodic table. All. you know that you wanted grams and the denominator because you want grams to cancel. Right? So, that's your first step. You are now at moles of calcium. So now you need to convert to Adams. You should do that by using avocados. Number one mole of calcium or one mole of anything Is equal to 6.2 Times 10 to the 23rd particles. In this case, those particles will be atoms of calcium. So moles of calcium will cancel. And now you just need to calculate our answer rounding it to three significant figures. Because the measurement you were given for the mass has three significant figures. So do 61.0 divided by 40.08. And multiply by 6.02 times 10 to the 23rd. Rounding that 2, 3 significant figures, that's 9.16 Times 10 to the 23rd atoms of calcium. And that is our final answer. 9.16 times 10 to the 23rd calcium atoms.