Answer:
C: francium-221
Explanation:
First of all to get a broader perspective, every isotope of francium usually undergoes decay to form astatine, radium, or radon.
Now, Francium-223 and francium-221 are it's only isotopes that occur in nature.
However, francium-221 is the one that undergoes alpha decay to produce astatine-217.
0.329 M copper (II) nitrate was reacted with 0.528 M potassium carbonate as follows: Cu (NO subscript 3 )subscript 2 italic (a q italic )space plus space straight K subscript 2 CO subscript 3 italic (a q italic )rightwards arrow CuCO subscript 3 italic (s italic )space plus space 2 thin space KNO subscript 3 italic (a q italic )Determine the percent yield if 163.9 mL of each reactant were allowed to react, and a mass of 4.883 g of solid were obtained.
Answer:
73.33% is the percent yield
Explanation:
Percent yield is defined as:
Actual yield (4.883g) / Theoretical yield * 100
Based on the reaction:
Cu(NO₃)₂(aq) + K₂CO₃(aq) → CuCO₃(s) + 2KNO₃(aq)
1 mole of copper nitrate reacts per mol of potassium carbonate.
To solve this question we must find limiting reactant. With limiting reactant we can find the theoretical moles of solid produced and its mass as follows:
Moles Cu(NO₃)₂:
0.1639L * (0.329mol / L) = 0.0539 moles
Moles K₂CO₃:
0.1639L * (0.528mol / L) = 0.0865 moles
As the reaction is 1:1, the limiting reactant is Cu(NO₃)₂.
1 mol of Cu(NO₃)₂ produces 1 mol of CuCO₃. That means theoretical moles produced are 0.0539 moles. And the mass is:
Mass CuCO₃ -Molar mass: 123.55g/mol-
0.0539 moles * (123.55g / mol) = 6.659g of CuCO₃ is the theoretical mass
And percent yield:
4.883g / 6.659g * 100
73.33% is the percent yieldIf I had 3.50 x 10 24molecules of Cl2 gas, how many grams is this?
Answer:
412 g Cl₂
General Formulas and Concepts:
Atomic Structure
Reading a Periodic TableMolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
[Given] 3.50 × 10²⁴ molecules Cl₂
[Solve] grams Cl₂
Step 2: Identify Conversions
Avogadro's Number
[PT] Molar Mass of Cl - 35.45 g/mol
Molar Mass of Cl₂ - 2(35.45) = 70.9 g/mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 3.50 \cdot 10^{24} \ molecules \ Cl_2(\frac{1 \ mol \ Cl_2}{6.022 \cdot 10^{23} \ molecules \ Cl_2})(\frac{70.9 \ g \ Cl_2}{1 \ mol \ Cl_2})[/tex][DA] Divide/Multiply [Cancel out units]: [tex]\displaystyle 412.072 \ g \ Cl_2[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
412.072 g Cl₂ ≈ 412 g Cl₂
what is the definition for domain bacteria?
Answer:
Domain is the............. highest taxonomic rank in the hierarchical biological classification system, ........above the kingdom level. There are three domains of life, the Archaea, the Bacteria,,,,,,,,, and the Eucarya.
Reword, taken off the internet.
Explanation:
The city of Annandale has been directed to upgrade its primary wastewater treatment plant to a secondary treatment plant with sludge recycle that can meet an effluent standard of 11 mg/l BOD5. The following data are available: Flow = 0.15 m3/s, MLSS = 2,000 mg/L. Kinetic parameters: K, = 50 mg/L, Hmax = 3.0 d-, kų = 0.06 d-1, Y = 0.6 Existing plant effluent BOD5 = 84 mg/L. a. Calculate the SRT (Oc) and HRT (0) for the aeration tank. b. Calculate the required volume of the aeration tank. c. Calculate the food to microorganism ratio in the aeration tank. d. Calculate the volumetric loading rate in kg BOD3/m3-d for the aeration tank. e. Calculate the mass and volume of solids wasted each day, when the underflow solids concentration is 12,000 mg/L. 10 A
classify each of the following reactions when only the reactants are given and fill in the products.
explain your answer for brainliest.
Answer:
CO2 + MgO
Explanation:
We want the number of each element on the Reactants (Left side) to be equal to the number of each element on the Product side (Right side).
Pls help ASAP it’s timing meeee!!!!!
What are all of the mole ratios of MgCl2 -> Mg+ Cl2
Answer:
2 moles
In words, 1 mole of Mg reacts with 2 moles of HCl to form 1 mole of MgCl₂ and 1 mole of H₂. The molar ratio of HCl to MgCl₂ is 2:1.
A group of elements with similar properties, which usually falls into columns on the periodic table. A.period b.ductile c.atomis d.family
What will change more solid NiCl2 is added
Terry, a student, performs a titration. He completes these steps as part of his titration procedure: 1. He cleans and rinses a burette with standardized base. 2. He fills the burette with standardized base solution. 3. He reads and records the initial burette volume. 4. He adds a base from the burette to an acid. 5. He observes a color change in the Erlenmeyer flask. 6. He stops the addition of base from the burette. 7. He reads and records the final burette volume. Which steps will provide information needed to calculate the volume of base needed to reach the equivalence point? A. 1 and 6 B. 3 and 7 C. 3, 4, and 6 D. 1, 2, and 7
Answer:
D
Explanation:
D is the answer because 2 is needed to know
Answer:
B) 3 and 7
Explanation:
i just took the test
If there are 1.55 x 1024 molecules of hydrogen peroxide (H2O2), what is the mass of the
sample?
Answer:
87.54 g of H₂O₂
Explanation:
From the question given above, the following data were obtained:
Number of molecules = 1.55×10²⁴ molecules
Mass of H₂O₂ =.?
From Avogadro's hypothesis,
6.02×10²³ molecules = 1 mole of H₂O₂
Next, we shall determine the mass of 1 mole of H₂O₂. This can be obtained as follow:
1 mole of H₂O₂ = (2×1) + (2×16)
= 2 + 32
= 34 g
Thus,
6.02×10²³ molecules = 34 g of H₂O₂
Finally, we shall determine mass of H₂O₂ that contains 1.55×10²⁴ molecules. This can be obtained as follow:
6.02×10²³ molecules = 34 g of H₂O₂
Therefore,
1.55×10²⁴ molecules
= (1.55×10²⁴ × 34)/6.02×10²³
1.55×10²⁴ molecules = 87.54 g of H₂O₂
Thus, 87.54 g of H₂O₂ contains 1.55×10²⁴ molecules.
Consider the following data on some weak acids and weak bases:
acid base
name formula Ka name formula Kb
hydrocyanic acid HCN 4.9 x 10^-10 hydroxylamine HONH2 1.1 x 10^-1
hypochlorous acid HCIA 3.0 x 10^-18 ethylamine C2H5NH2 6.4 x 10^-4
Use this data to rank the following solutions in order of increasing pH. In other words, select a '' next to the solution that will have the lowest pH, a '' next to the solution that will have the next lowest pH, and so on.
a. 0.1 M HONH3Br
b. 0.1 M NaNO3
c. 0.1 M C2H5NH3Cl
d. 0.1 M NaF
Answer:
a < c < b < d
Explanation:
The weak acid with the lowest pKa will be the most acidic. In the other way, the conjugate base which the acid is weakest will be strongest.
The weak base with the lowest pKb will be the most basic. And the conjugate base of the weakest base will be a strongest acid.
Using the values:
Ka HCN = 4.9x10⁻¹⁰
Kb HONH2 = 1.1x10⁻⁸
Ka HClA 3.0x10⁻⁸
Kb C2H5NH2 = 6.4x10⁻⁴
The NaNO3 is the conjugate base of a strong acid as HNO3. That means its solutions are almost neutral
The HONH3Br is the conjugate acid of a weak base. Its solutions will be acidics
C2H5NH3Cl is the conjugate acid of a weak base as ethylamine, its solutions will be acidic.
As ethylamine has a lower pkb than hydroxylamine, the conjugate acid of hydroxylamine will be more acidic.
NaF is the conjugate base of a weak acid as HF. Its solutions will be basics
The order in increasing pH is:
HONH3Br < C2H5NH3Cl < NaNO3 < NaF
a < c < b < dMy swimming pool is rectangular (16 feet by 34 feet) and has a depth of 6 feet. Lets imagine that my pool water is full to the top and is heated by a laser that emits photons with a wavelength of 520 nm. The starting temperature of my pool is a chilly 52 degrees Celsius. How many moles of photons would be required to heat the pool to a balmy 80 degrees Celsius
Answer:
Number of moles of photons required = 5.04 × 10⁴ moles
Explanation:
The energy of a photon can be calculated from Planck's equation E = hc/λ
Where h = 6.63 × 10-³⁴ Js and c, the velocity of light = 3.0 × 10⁸ m/s
Energy of one mole of photons = N₀ × hc/λ
wavelength of photon, λ = 520 nm = 5.20 × 10-⁷ m
Energy of one mole of photons = 6.02 × 10²³ × 6.63 × 10−³⁴ × 3 × 10⁸/5.20 × 10-⁷
Energy of one mole of photons = 2.30 × 10⁵ J/mol
Energy required to raise the temperature of a given mass of a substance, E = mcΔT
Where m is mass of substance, c is specific heat capacity, ΔT is temperature difference
Mass ofnwternin the pool = volume × density
Volume of water = Volume of swimming pool
Volume of water = 16 × 34 × 6 ft³ = 3264 ft³
1 ft³ = 28316.8 cm³; 3264 ft³ = 28316.8 × 3264 = 92426035.2 cm³
Density of water = 1 g/cm³
Mass of water = 92426035.2 cm³ × 1 g/cm³ = 92426035.2g
ΔT = 80°C - 50°C = 30°C, c = 4.18 J/g/K
Energy required to raise 92426035.2 g water by 30° C = 92426035.2 × 4.18 × 30
Energy required = 1.16 × 10¹⁰ J
Hence, number of moles of photons required = 1.16 × 10¹⁰ J/2.30 × 10⁵ J/mol
Number of moles of photons required = 5.04 × 10⁴ moles
Excessive use of chemical fertilizer causes chemical pollution.how?
Answer:
Chemical fertilizers contain various chemicals that cause harm to soil and water.
Explanation:
Chemical fertilizers contain various chemicals such as phosphates, nitrates which can cause water pollution. Eutrophication caused by the environmental nitrogen and phosphorous that causes rich minerals and chemicals in the water.
These can cause excessive growth of the algae and phytoplankton that will cause depletion of the oxygen from the water body and organisms will die due to this.
करताह!
गर्मियों में घड़े का जल ठंडा क्यों होता है?
Answer:
I don't understand the question
Explanation:
what is your name
Describe the effects lenses have on light and their possible technological applications.
Answer:
lenses is used to refract light inward or outward
there are two type of lenses. Concave and convex lense
Convex lense converge ray of light
Concave lense diverge ray of light
useful application =:
=> camera
=> flashlight
=> lasers
=> Binoculars and Telescope
hope it helps
Answer:
Explanation:
Lenses are made of glass or other transparent materials for light. They are optically dense so light slows down on entering it. It is called refraction which bends the light on entering and leaving the lenses.
Refraction by lenses can be used for all kinds of optical applications, e.g. camera, telescope, magnifying glasses, solar heating.
Will give brainliest
In an experiment, the molar mass of the compound was determined to be 228.276 g/mol. What is the molecular formula of the compound?
How does publishing in scientific journals help ensure that science leads to
reliable results?
A. It allows results to be reviewed and reproduced by other
scientists.
B. It allows the public to decide if science is worthwhile.
C. It shows which experiments are the most popular with scientists.
D. It gives scientists a reason to do more experiments.
Answer:
A. it allows results to be reviewed and reproduced by other scientists.
How many Liters are in 98.2 moles of neon?
Answer:
2200 L
Explanation:
There are 22.4 L in 1 mole of neon so if you have 98.2 L, then you have 98.2 mole x (22.4 L/mole) = 2200 L of neon.
A 3mL sample of a 200 Molar solution is left open on a lab
counter for two weeks, after which the concentration of the solution is 6 M. What is the new volume of the solution?
Answer: New volume of the solution is 100 mL.
Explanation:
Given: [tex]V_{1}[/tex] = 3 mL, [tex]M_{1}[/tex] = 200 M
[tex]M_{2}[/tex] = 6 M, [tex]V_2[/tex] = ?
Formula used to calculate the new volume of solution is as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}[/tex]
Substitute the values into above formula as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}\\200 M \times 3 mL = 6 M \times V_{2}\\V_{2} = \frac{200 M \times 3 mL}{6 M}\\= 100 mL[/tex]
Thus, we can conclude that new volume of the solution is 100 mL.
Select the correct answer.
What is the molecularity of this elementary step?
A+ A+B-->C+D
A.
unimolecular
B.
bimolecular
c.
trimolecular
D.
tetramolecular
Answer: C not really sure thoo
where do you think water vapor in air comes from?
You have a cold gas of atoms, and you observe that if you shine light consisting of photons with energy 10 eV through the gas, some free electrons are observed, implying that a photon of this energy is able to ionize an atom in the gas. (a) If you find that the emitted electrons from the gas have a kinetic energy of 1 eV, what is the ionization energy of the cold atom
Answer:
Ionization Energy = 9 eV
Explanation:
If we apply the law of conservation of energy to the given situation, we will get the following equation:
[tex]Energy\ of\ Photon = Ionization\ Energy + Kinetic\ Energy\ of\ Electron\\[/tex]
where,
Energy of Photon = 10 eV
Ionization Energy = ?
Kinetic Energy of Electrons = 1 eV
Therefore,
[tex]10\ eV = Ionization\ Energy + 1\ eV\\Ionization\ Energy = 10\ eV - 1\ eV[/tex]
Ionization Energy = 9 eV
A scientist observes the cells of a newly discovered animal under a
microscope. Which of the following cell parts is the scientist likely to find?
A. Cell membrane, chloroplasts, and a nucleus
B. Cell wall, cell membrane, and ribosomes
O C. Cell wall, chloroplasts, and lysosomes
D. Cell membrane, ribosomes, and a nucleus
Answer:
D
Explanation:
The rest have characteristics of a plant cell
When 15. 3 g NaCl reacts with 81.70 g Pb(NO3)2, sodium chloride is the limiting reactant, according to the balanced equation below. How many grams of lead (II) nitrate will remain after the reaction stops?
2 NaCl + 1 Pb(NO3)2 → 2 NaNO3 + 1 PbCl2
Answer:
[tex]m_{Pb(NO_3)_2}^{leftover}=38.34g[/tex]
Explanation:
Hello there!
In this case, given the chemical reaction by which the sodium chloride reacts with lead (II) nitrate and the former is the limiting reactant, it is possible to calculate the mass of lead (II) nitrate that are actually consumed according to the 2:1 mole ratio between them:
[tex]m_{Pb(NO_3)_2}=15.3gNaCl*\frac{1molNaCl}{58.44gNaCl}*\frac{1molPb(NO_3)_2}{2molNaCl} *\frac{331.21gPb(NO_3)_2}{1molPb(NO_3)_2} \\\\m_{Pb(NO_3)_2}=43.36gPb(NO_3)_2[/tex]
Thus, the leftover of lead (II) nitrate is:
[tex]m_{Pb(NO_3)_2}^{leftover}=81.70g-43.36g\\\\m_{Pb(NO_3)_2}^{leftover}=38.34g[/tex]
Best regards!
How will the temperature change if you increase the mass of the gas molecules?
The temperature of a gas sample rises, the molecules quicken, and as a result, the root mean square molecular speed rises.
What is meant by temperature?Degree of warmth or coolness determined by a specific scale
The temperature of a gas sample rises, the molecules quicken, and as a result, the root mean square molecular speed rises.
In a gas, the speed of the molecules is inversely related to the molar mass of the gas and inversely proportional to temperature.
The rate of diffusion is inversely related to the square root of the gas's molar mass, according Graham's law of Diffusion.
To learn more about temperature, refer to the below link:
https://brainly.com/question/13122916
# SPJ2
How many liters would you need to make a 0.8 M solution with 20 grams of lithium chloride?
Answer:
0.5875L
Explanation:
concentration = mole/ volume
n(LiCl) = 20 / (7 + 35.5) = 0.47 mol
volume = mole / conc.
volume = 0.47 /0.8
= 0.5875 dm³ = 0.5875L
Which of the following accurately describes the function of the muscular
system?
O A. To prevent and fight disease
B. To provide support for the body
C. To get rid of wastes and excess water
D. To allow the body to move
g A student determines the number of moles of water in a hydrated metal oxide by weighing a clean, dry crucible and lid while the crucible is empty, then reweighing the crucible and lid with a sample of the hydrate, heating the crucible and lid with a Bunsen burner and then reweighing the crucible and lid with the sample after cooling to room temperature. Which error will result in too high a value for the amount of water of hydration
The question is incomplete, the complete question is;
A student determines the number of moles of water in a
hydrated metal oxide by weighing a clean, dry crucible
and lid while the crucible is empty, then reweighing the
crucible and lid with a sample of the hydrate, heating the
crucible and lid with a Bunsen burner and then
reweighing the crucible and lid with the sample after
cooling to room temperature. Which error will result in
too high a value for the amount of water of hydration?
(A) The heating is conducted only once instead of the
three times recommended by the procedure.
(B) The lid is left off the crucible when it is weighed
with the hydrated oxide.
(C) The metal oxide reacts partially with oxygen in the
air, forming a compound in a higher oxidation state.
(D) Some of the heated oxide is spilled from the crucible
before it can be weighed.
Answer:
(D) Some of the heated oxide is spilled from the crucible
before it can be weighed.
Explanation:
It is possible to determine the number of moles of water in a hydrated metal oxide by weighing a clean, dry crucible and lid while the crucible is empty, then reweighing the crucible and lid with a sample of the hydrate. The crucible and lid with the sample are heated, cooled and reweighed.
As this process is going on, suppose some of the heated oxide is spilled from the crucible, then the mass of heated or anhydrous oxide decreases leading to a consequent increase in the number of moles of water in the hydrated metal oxide, hence the answer above.
The too high a value for the amount of water of hydration error is occur due to heating of given hydrated sample.
What is hydrated compounds?
Hydrated compounds are those compounds in which water molecule is present with the normal compound.
To get the correct value of weight of hydrated compound, first we have to weigh the empty crucible and lid and then with sample of compound in the crucible and lid. After this substract empty weigh of crucible & lid from the sample-crucible-lid weigh. If we substract the weigh from heated sample crucible and lid, then we get the error because the hydrated water molecule may decompose due to heating and moles of water increases.
Hence, error will occur if we heat the sample.
To know more about hydrated compound, visit the below link:
https://brainly.com/question/16275027
What is the energy of a photon?
A. A photon has no energy.
B. The energy of a photon is hxc.
c. The energy of a photon is hx 2.
D. The energy of a photon is h* f.
