Do you round before or after multiplying the molecular mass of an element for example I multiplied C12 which is 12*12.011 and got 144.32 (amu) but the correct answer was 144.12 (amu) and that was found by doing 12*12.01 ?

Q: A sample of a compound made of elements A and B was analyzed to contain 2.456 g of A and 1.714 g of…

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Q: 3. A mixture containing only AgCl (FW 143.32) and AgBr (FW 187.77) weighs 2.000g. It is…

A: Here we are required to find the percentage of AgCl and AgBr in 2 gm of sample

Q: Express your answers to at least 5 significant figures. The mass of one mole of boron is 10.811 g.…

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Q: The atomic weight of sulfur is 32 g/mol. By using the result from (2), write the molecular formula…

A: According to the Bartleby guidelines we have to answer only one question so please submit different…

Q: Which scale is most useful for reporting data from the spectrometer? Why?

A: The two scales used for analysis in UV spectroscopy is percent transmittance and absorbance.

Q: Chemistry (1= T15HW Question 5 Homework Unanswered O Determine the percent by mass of both magnesium…

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Q: Be sure to answer all parts Hew many moles of cobalt (Ce) stoms are there la 2.00 x 10 (200 hillion)…

A: Given, Number of Co atom = 2.00×10^9  Avogadro's no. = NA= 6.023×10^23

Q: Use the References to access important values if needed for this question. Calculate the number of…

A: Volume of Ethane gas = 474 cm3 Temperature = 0 ◦C Or 273.15 K Pressure = 1 atm Density = 1.34 × 10-3…

Q: Diamonds are made of pure carbon. How much does a diamond weigh if it is composed of 1.06x1023…

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Q: Which of the following values is in "SOE" for the compound named iron(III) oxalate? A) 167.4 g Fe B)…

A: The molecular formula of iron(III) oxalate is Fe2(C2O4)3  Hence 1 mole of Fe2(C2O4)3 has 1) 2 Atoms…

Q: 7. State the chemical composition (constituent elements and number of atoms of each element) for a…

A: Given  is a molecule of citric acid whose molecular formula is C3H4OH(COOH)3.  Chemical composition…

Q: PID "6A3919 2. Show the calculation for the number of atoms of copper contained in 0.0000282 grams…

A: Since you have posted a question with multiple sub-parts ,we will solve first three sub-parts for…

Q: What is the ratio of hydrogen atoms (H) to oxygen atoms (O) in 2 L of water? Enter the simplest…

A: Dear student since you have asked multiple questions but according to guidelines we will solve 1st…

Q: You are given a sample that contains a mixture of the following two arsenic-containing minerals:…

A: Metals and non metals are present in nature in their minerals. They are extracted from these…

Q: Background Size A A A NaNO, + PbO > Pb(NO3)2 Na,0 +.

A: Since you have asked multiparts, we will solve the first three subparts for you. If you want any…

Q: What element has 7.767 x 1017 atoms in 6.57 x 10-5 g of material?   Group of answer choices A.…

A: Given data is: Mass of material = 6.57×10-5 g Determine the element having 7.767 x 1017 atoms in…

Q: Question 1

A: Balanced chemical equation of a reaction is written according to law of conservation of mass. Thus,…

Q: Using dimensional analysis, convert 5.7 moles of Fluorine into atoms. (1 mol = 6.02 x 1023). Round…

A: We know that, 1 mole = 6.02 x 10^23 atoms So, Number of atom = Number of miles x ( 6.02 x 10^23)

Q: 2.48g of hydrated copper(ii)chloride (CuCl2.xH2O) were heated to constant mass. 1.96g of anhydrous…

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Q: 28. What is the coefficient of H₂O when the following equation is properly balanced with smallest…

A: A balanced chemical equation is the one that contains the same count of different types of atoms on…

Q: What is the percent by mass of hydrogen in Ca(OH)2? Group of answer choices 2.72 % 1.36% 21.6 %…

A: % by mass basically tells about the concentration of one element present in the mixture. The formula…

Q: A compound is found to be 30.45% N and 69.55 % O by mass. If 3.01 g of this compound occupy 780 mL…

A: Empirical Formula :- When we write the chemical formula of a compound with the simplest ratio or…

Q: How many sigfigs does this number have 0.021?

A: Rules:- All non-zero digits are significant. Zeros between non-zeros are significant. Trailing…

Q: What is the mass to charge ratio of a propane ion (C3H3*) if one of the carbon atoms is a 13C and…

A: The mass to charge ratio of the propane ion (C3H8+) can be calculated by taking the sum of the mass…

Q: Tungsten is a very dense metal (19.3 g/cm3) with extremely high melting and boiling points (3370ºC…

A: Let the mass of CaWO4 is w gram. As given  Mass of W in CaWO4 =mass of W in 657g of FeWO4  Moles of…

Q: A  sample of washing soda (a hydrate of sodium carbonate) has the formula Na2CO3.xH2O. When 2.558 –g…

A: The value of x can be calculated by knowing the moles of Na2CO3 and H2O present in the Na2CO3.xH2O…

Q: Question attached

A: Mass of water is calculated as follows: Hydrate = anhydrous salt + watermass of water=mass of…

Q: If a sample of B10H12[N(CH3)3]2 is found to contain 7.48 · 1020 B atoms how many N atoms are…

A: Given: number of B atoms = 7.48×1020 atoms

Q: Each atom in a crystal of aluminum metal occupies a theoretical cube that is 0.255 nm on a side. If…

A: side of the cube = 0.255 nm = 0.255 x 10-7 cm1nm = 10-7cmVolume of the theoretical cube = (side)3 =…

Q: What number is 5.12234E3 in standard form?

A: Given that;     A number 5.12234E3 , we have to convert in into standard form.

Q: Determine the mol H2O/mol CaSO4 if you have the following data to two decimal places (MM H2O =18.02…

A: Moles are ratio of mass to molar mass of substance.

Q: How many atoms of sulfur are in 264 g of Na:S:O: ? Atomic weights: Na=22.99, S=32.07, 0=15.99. Input…

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Q: 2.The only empirical formula is: Group of answer choices A, C6H14 b, C2H4 c, C8H16 d, 1. C7H19

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Q: How many atoms of fluorine are in 1.1E0 moles of CF4? Respond with the correct number of significant…

A: Given, The number of atoms of fluorine are in 1.1E0 moles of CF4 is :

Q: Up late, a (tired) engineer calculated the molar mass of nitroglycerin (C3H5N3O9) to be 196.2 g/mol,…

A: Nitroglycerin = C3H5N3O9  Molar mass of nitrohlycerin = 196.2 g/mol  Percent error = ?

Q: 9) An experiment was done in which zinc was reacted with hydrochloric acid in a vessel to make…

A: Since moles = mass / molar mass And mass of Zinc = mass of evaporating dish + zinc ( before the…

Q: The compound NHxNO3 contains 5.04% hydrogen by mass. What is the value of x? Enter your response as…

A: Given  % Hydrogen =  5.04 %  formula of compound  = NHxNO3 Value of x = ?

Q: Calculate the number of atoms of hydrogen (H) in 394 cm³ of the colorless gas butane at 25 °C and…

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Q: How many atoms of sulfur are in 499 g of Na₂S₂O₃ ?

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Q: Consider a random mixture containing 7.00x106 particles of Na2CO3 and 5.00x107 particles of K2CO3.…

A: Given: The number of particles of Na2CO3 in the mixture = 7.00 × 106 particles. And the number of…

Q: hlorobenzene (MW 112.56, d 1.11) is a chemical solvent. If you need 0.77 moles of chlorobenzene,…

A: Chlorobenzene is a solvent with molecular formula = C6H5Cl Molecular mass = 112.56 g/mol Density =…

Q: Use the References to access important values if needed for this question. Calculate the number of…

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Q: What do the formula H2O and H2O2 tell about composition? Are they the same compounds? Justify your…

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Q: 5. Perform the following conversions. 1.73 тol NaОН — g Na0H %3D 0.274 g NH3 = mol NH3 76.2 g Си 3…

A: The number of moles is a ratio of the mass of a substance to the molar mass of the substance.…

Q: and sighinicait ngur es. 1. 18 x 10-19– 5.21 x 10-20 O4.03 x 10-20 O4.0x 1020 6.59 x 10-20

A: For addition or subtraction of significant figures, we Round off the sum or difference to the same…

Q: 6.61 x1019 molecules of hydrogen gas,(H2) are equal to how many grams of hydrogen gas?

A: SOLUTION 6.022×1023 molecules of H2 gas is equal to 1 mol of H2 gas. 1 molecule of H2 gas is…

Q: FHOW is it different? 2.80 Consider a mixture of 10 billion O2 molecules and 10 billion H,…

A: Molecules are particles that are formed by two or more atoms.

Q: Suppose that a student dehydrates strontium chloride hydrate and reports the formula as SrCl2 •…

A: According to the question, a student dehydrates strontium chloride hydrate and reports the formula…

Q: Each time you inhale, you take in about 5.0x10^2ml (two significant figures) of air, each milimeter…

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Atoms and Molecules

An atom is the smallest unit of an element that possesses all the properties of that particular element. Molecules are the smallest unit of a substance that possess all the properties of that particular substance.