Answer:
See explanation
Explanation:
a. I can conclusively tell if the crown was made of gold by measuring its density. First the mass of the crown is measured on a weighing balance. The crown is now put into a given volume of water and the volume of water displaced is accurately measured. The density of the crown is computed as mass/volume of fluid displaced. If the density of the crown is 19.3 g/mL, then it is made of solid gold.
b) When less valuable metals such as bronze or copper is mixed with gold in the crown, the density of the crown decreases and the crown becomes more brittle.
c) An object will float in a liquid when the density of the object is less than the density of the liquid. Hence the tendency of an object to float in a liquid depends on the density of the object and the density of the liquid.
d) Even though i do not know the results from your experiment but as regards the decision as to whether the object will float in the given liquid or not, reference must be made to the measured density of the object as well as the given density of the liquid. If the object is less dense (from values of density obtained from the experiment) than the liquid, then the object will float in the liquid and vice versa.
2. Combining 0.242 mol Fe2O3 with excess carbon produced 10.2 g Fe.
Fe2O3+3C⟶2Fe+3CO
(a) Actual yield of Fe mole
(b) percentage mole
(c) theoretical yield of iron mmoles
actual yield = 0.182 mole
theoretical yield : 0.484 mole
percentage mole(% yield)=37.6%
Further explanationPercent yield is the comparison of the amount of product obtained from a reaction with the amount you calculated
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients
Reaction
Fe₂O₃+3C⟶2Fe+3CO
a. actual yield of Fe mole
10.2 g produced
[tex]\tt mol~Fe=\dfrac{10.2}{56}=0.182[/tex]
b. percentage mole and theoretical yield
0.242 mol Fe₂O₃ = 2 x 0.242 mol Fe = 0.484 mol (theoretical yield)
percentage yieldpercentage mole)
[tex]\tt \dfrac{0.182}{0.484}=0.376=37.6\%[/tex]
From the following heats of reaction,
2C (graphite) + H2 (g) -->C2H2 (g) H = 227 kJ
6C (graphite) + 3H2 (g) -->C6H6 (l) H = 49 kJ
calculate the heat for the reaction
3C2H2 (g) -->C6H6 (l)
A. 26.7 kJ
B. -26.7 kJ
C. -178 kJ
D. 178 kJ
E. -632 kJ
F. 632 kJ
Answer:+178
Explanation:
The heat of the reaction for the following reactions is 178 kJ. the correct option is D.
What is the heat of the reaction?The heat that is added or removed during a chemical reaction is called the heat of reaction.
It is also called the enthalpy of the reaction.
The heat is absorbed or released to maintain the temperature of the reaction.
The enthalpy can be calculated by subtracting the enthalpy of the product from the enthalpy of the reactant.
Thus, the correct option is D.
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Which products are formed when aluminum is added to a silver chloride solution? Use the activity series below if needed. Al> Mn > Zn>.Cr > Fe > Cd> Co > Ni > Sn > Pb>H> Sb > Bi > Cu> Ag > Pd >Hg > Pt O none O only AICI3 O AlCl3 and Ag O AIAg3 and Cl2
Answer:
AlCl3 and Ag
Explanation:
Edge 2020
The products formed when aluminum is added to a silver chloride solution are "AlCl3 and Ag".
The reaction of aluminum and silver chloride is a single substitution type of reaction that is expressed as follows: Al (s) + 3AgCl (aq) = AlCl3 (aq) + 3Ag (s)When aluminum is added to the silver chloride solution, the cations are exchanged in the process forming AlCl3 and Ag.
Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.Chemical reactions are an integral part of technology, culture, and indeed of life itself. Burning fuels, smelting iron, making glass and pottery, brewing beer, and making wine and cheese are among many examples of activities incorporating chemical reactions that have been known and used for thousands of years. Chemical reactions abound in the geology of Earth, in the atmosphere and oceans, and in a vast array of complicated processes that occur in all living systems.Learn more about chemical reactions
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Is SO3 ionic or ionic using the stock system or molecular
Answer:
Molecular
Explanation:
Using the rules for the nomenclature for naming binary covalent (molecular) compounds, the compound SO3 is named sulfur trioxide. The prefix tri- indicates that the oxygen has a subscript of 3 and that a molecule of sulfur trioxide has three oxygen atoms.
How do hurricanes form? How do hurricanes form?
a Hurricanes form when winds circulate about a column of cool air.
b Hurricanes form when two warm fronts meet over the ocean
c Hurricanes form when warm air over the equator mixes with cold air from the poles
d Hurricanes form as a result of rising warm air and circulating winds
Answer:
D. Hurricanes form as a result of rising warm air and circulating winds
Explanation:
Which pair of elements would you expect to have similar properties?
Li and Fe
At and F
F and o
Ge and As
2. Which of the following is NOT a necessary input for the process of photosynthesis?
A. CO2 (carbon dioxide)
B. Sunlight
C. H20 (water)
D. O2 (oxygen)
The answer option which is not a necessary input for the process of photosynthesis is: D. [tex]O_2[/tex] (oxygen)
Photosynthesis can be defined as a biological and chemical process through which living organisms such as green plants, transform light energy (sunlight) into chemical energy.
Basically, both sunlight, carbon dioxide ([tex]C0_2[/tex]) and water ([tex]H_2O[/tex]) contained in the Earth's atmosphere plays a significant role in photosynthesis because they serve as an input.
Hence, the necessary input for the process of photosynthesis to take place include the following:
Water ([tex]H_2O[/tex]) Sunlight (light energy).Carbon dioxide ([tex]C0_2[/tex]).In conclusion, [tex]O_2[/tex] (oxygen) is an end product (output) of photosynthesis rather being an input.
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6.0 L of a gas exert a pressure of 2.5 atm. When the pressure is increased 2 points
to 10.0 atm, what is the new volume of the gas?
O 1.0L
O 1.5L
O 1.7L
O 25L
what is the device to use to measure a potential difference in a circuit called?
Answer:
c. Voltmeter
Explanation:
PLATO LIVES MATTER
How many kilpgrams are in 2.71x10^22 molecules of CO2
Answer:
mass of 1 molecule of CO2=44 g
mass of 2.71*10^22 of CO2=2.71*10^22*44=1.2*10^24g
now to convert grams into kilogram we know that
1000 g=1kg
1.2*10^24=1.2*10^24/1000=1.2*10^21
According to Avogadro's number concept,there are 1.979×10[tex]^-3[/tex] kilograms in 2.71 ×10²² molecules of CO₂.
What is Avogadro's number?Avogadro's number is defined as a proportionality factor which relates number of constituent particles with the amount of substance which is present in the sample.
It has a SI unit of reciprocal mole whose numeric value is expressed in reciprocal mole which is a dimensionless number and is called as Avogadro's constant.It relates the volume of a substance with it's average volume occupied by one of it's particles .
According to the definitions, Avogadro's number depend on determined value of mass of one atom of those elements.It bridges the gap between macroscopic and microscopic world by relating amount of substance with number of particles.
Number of atoms can be calculated using Avogadro's number as follows: mass/molar mass×Avogadro's number. Mass is calculated as, number of molecules/Avogadro's number×molar mass
Substitution in above formula gives, mass=2.71×10²²/6.023×10²³×44=1.979 g or 1.979×10[tex]^-3[/tex] kg.
Thus, there are 1.979×10[tex]^-3[/tex] kg in 2.71×10²² molecules of carbon dioxide.
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Which numerical setup can be used to calculate the
atomic mass of the element bromine?
Answer:
From the numerical steps highlighted under explanation, the average atomic mass of bromine is 79.91 u
Explanation:
The steps to be taken will involve;
1) Find the number of isotopes of bromine.
2) Identify the atomic mass and relative abundance of each of the isotopes.
3) Multiply the atomic mass of each of the isotopes by their corresponding values relative abundance value.
4) Add the value in step 3 above to get the average atomic mass of bromine.
Now;
Bromine has 2 isotopes namely;
Isotope 1: Atomic mass = 78.92amu and a relative abundance of 50.69%.
Isotope 2: Atomic mass = 80.92amu and a relative abundance of 49.31%.
Using step 3 above, we have;
(78.92 × 50.69%)
And (80.92 × 49.31%)
Using step 4 above, we have;
(78.92 × 50.69%) + (80.92 × 49.31%) ≈ 79.91 u
The atomic mass of bromine has been calculated as 79.9062 amu.
The relative atomic mass of the element has been given as the mass of each isotope with respect to their abundance.
The atomic mass has been given as:
[tex]amu=\sum mass\;\times\;\% Abundance[/tex]
The available isotopes of Bromine have been:
Isotope 1 = 78.92 amu, and 0.5069 % abundance
Isotope 2= 80.92 amu, and 0.4931 % abundance
Submitting the values for the atomic mass unit of bromine ([tex]amu_{\text{Br}}[/tex]):
[tex]amu_{\text {Br}}= (78.92\;\times\;0.5069)\;+\;(80.92\;\times\;0.4931)\\amu_{\text{Br}}=40.0045\;+\;39.9016\\amu_{\text{Br}}=79.9062[/tex]
The atomic mass of bromine has been calculated as 79.9062 amu.
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Identify the titration curve for a monoprotic weak acid titrated with a strong base.
Answer:
Titration is a technique to determine the concentration of an unknown solution. As illustrated in the titration setup above, a solution of known concentration (titrant) is used to determine the concentration of an unknown solution (titrand or analyte).
Typically, the titrant (the solution of known concentration) is added through a burette to a known volume of the analyte (the solution of unknown concentration) until the reaction is complete. Knowing the volume of titrant added allows us to determine the concentration of the unknown analyte. Often, an indicator is used to signal the end of the reaction, the endpoint. Titrant and analyte is a pair of acid and base. Acid-base titrations are monitored by the change of pH as titration progresses.
Let us be clear about some terminologies before we get into the discussion of titration curves.
The density of osmium (the densest metal) is 22.57 g/cm3.
What is the mass of a block of osmium with dimensions:
4.22 cm x 3.62 cm x 1.41 cm?
Answer: mass = 485 grams approximately
=======================================================
Work Shown:
First we need the volume of the block
volume = (length)*(width)*(height)
volume = (4.22)*(3.62)*(1.41)
volume = 21.539724
volume = 21.5 cubic cm
I'm rounding to three sig figs because each of the dimensions are to three sig figs.
--------------------------
Now turn to the formula
density = mass/volume
This can be rearranged to
mass = density*volume
Plug in the given density and the volume we found earlier to get
mass = density*volume
mass = (22.57)*(21.5)
mass = 485.255
mass = 485 grams
I'm rounding to three sig figs because it's the smaller sig fig count of 22.57 and 21.5
Tumu’s class was given an assignment to feature a scientist that contributed to the development of the cell theory. The class decided to use images to feature the scientist of their choice.
Which image would Tumu most likely use in his assignment to feature Rudolf Virchow?
the magnified shapes of cells in a piece of cork
the different cells that make up a plant leaf
the types of cells at work in the human body
the way root cells reproduce to increase root length
Answer:
The types of cells at work in the human body
Explanation:
Rudolf Virchow was a German physician who is known as the father of modern pathology. He contributed to the development of the cell theory by concluding that all cells come from preexisting cells. This led to the conclusion that diseases occur at the cellular level, which allowed scientists to diagnose diseases more accurately.
Considering that Virchow analyzed human cells, the image that Tumu would be most likely to use in his assignment is the one of the types of cells at work in the human body.
Answer:
D the way root cells reproduce to increase root length
Explanation:
Have a good day!
Convert 98.5 Pa into mm Hg. (133.32 Pa = 1.00 mm Hg)
Question 1 of 10
In which state of matter do the particles move independently of one another?
A. Amorphous solid
B. Gas
C. Crystalline solid
D. Liquid
Answer:
Gas (B)
Explanation:
How many grams of oxygen gas will be produced when 2.50 moles of potassium chlorate is decomposed?
Answer:
[tex]m_{O_2}=120gO_2[/tex]
Explanation:
Hello!
In this case, since the decomposition of potassium chlorate is:
[tex]2KClO_3\rightarrow 2KCl+3O_2[/tex]
We can see a 2:3 mole ratio between potassium chlorate and oxygen (molar mass 32.0 g/mol), thus, via stoichiometry, we compute the mass of oxygen that are produced by the decomposition of 2.50 moles of this reactant:
[tex]m_{O_2}=2.50molKClO_3*\frac{3molO_2}{2molKClO_3} *\frac{32.0gO_2}{1molO_2}\\\\m_{O_2}=120gO_2[/tex]
Best regards!
Which of the following is chemical property?
Question is in the picture help ASAP please
Answer:
C
Explanation:
Which of these statements best answers the question: What is art?
Answer:
You didn't provide any statements. If it is an option, art is a form of expression. Something created from imagination that expresses the thoughts and emotions of the artist.
The statement that best answers the question: What is art is that—Art is a form of visual language. Therefore, the correct option is A.
What is an art?Art is a diverse range of human activities and products that are created with the intention of expressing the imagination, emotions, or ideas, or to make a statement, in a visually appealing way.
Art can take many forms, including visual arts (such as painting, sculpture, and photography), performing arts (such as music, dance, and theater), and literary arts (such as poetry and prose).
It is typically seen as a form of communication and can be used to convey ideas, emotions, or political, social or cultural messages. It can also be used to simply evoke a response or emotion in the viewer, or to create a sense of beauty or aesthetic enjoyment. Therefore, the correct option is A.
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The question is incomplete, but most probably the complete question is,
Which of these statements best answers the question: What is art?
A. Art is a form of visual language.
B. Art is a form of written language.
C. Art is a form of spoken language.
D. Art is a form of dance language.
During bromination using NBS, the addition product is not observed because the rate of addition is _______than the rate of the chain propagation steps.
Answer:
slower
Explanation:
NBS is used in place of Br2 during bromination because the use of Br2 tends to result in the formation of a large concentration of the addition product. This is because, the Br2 interacts with the double bond to yield only the dibromide (addition product).
The usefulness of NBS lies in the fact that it provides a lower concentration of Br2, and such that the rate addition is slower than the chain propagation steps. Only the monobromination product is observed
The low concentration of Br2 allows the free-radical reaction to out-compete the alkene addition reaction.
Please help on the image below.
Heat capacity of Calorimeter = 10.7 J/°c
Further explanationHeat lost=Heat gained
Q in = Q out
-Q lost(hot water)=Q gained (cold water+calorimeter)
-m.c.Δt=m.c.Δt+C.Δt
[tex]\tt \rightarrow -50\times 4.18\times (32.7-43)=50\times 4.18\times (32.7-22.9)+(32.7-22.9)\times C_{cal}\\\\\rightarrow 2152.7=2048.2+9.8\times C_{cal}\\\\104.5~J=9.8\times C_{cal}\\\\C_{cal}=\dfrac{104.5}{9.8}=10.7~J/^oC[/tex]
What is the mass, in grams, of 2.3 moles of gold?
Answer:
453.031g
Explanation:
atomic mass (molar mass)- 196.97g/m
2.3(196.97)=453.031
Identify the molecule with the strongest intermolecular force.
C6H6
OF2
CHCl3
H2O
Answer:
C6H6 has the strongest intermolecular force
i think
Answer:
H2O
Explanation:
Because it is a hydrogen bond which is said to be the strongest bond between the H and a N,O, or F combination
Urgent help me please answer it if you know it
if a student added water to her cola what change would you expect to see in the ph level
Answer:
You would expect it to go down
Explanation:
This is because she is essentially watering down, causing the Ph level to go down too.
If a student added water to her cola, then the pH level is low. This is due to the fact that she is essentially diluting, which lowers the pH level as well.
What is pH ?The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality. Acidity is indicated by pH values below 7, whereas baseness is shown by pH values above 7. In reality, pH is a measurement of the proportion of free hydrogen and hydroxyl ions in water.
pH stands for "Potential of Hydrogen" in its full form. The negative logarithm of the concentration of H+ ions is known as pH. As a result, the meaning of pH is defined as the strength or power of hydrogen.
A solution's pH is a significant indicator of its chemical composition. The pH can affect how readily available nutrients are, how biological processes work, how bacteria behave, and how chemicals behave.
Thus, If a student added water to her cola, then the pH level is low.
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How does body temperature, energy level, and water level affect a person’s ability to survive?
An object has a mass of 3.50 grams and a density of 5.61 g/mL. What is the volume of this object? *
Answer:
0.62 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\[/tex]
From the question we have
[tex]volume = \frac{3.50}{5.61} \\ = 0.6238859...[/tex]
We have the final answer as
0.62 mLHope this helps you
Calculate the pH after 20.0% (by moles) of the benzoic acid is converted to benzoate anion by addition of a strong base. Use the dissociation equilibrium to calculate the pH. pH = ________
Answer:
pH = 4.79
Explanation:
The equilibrium of benzoic acid, BH, is:
BH ⇄ B⁻ + H⁺
Where B⁻ is benzoate anion
Where the dissociation equilibrium, Ka, is:
Ka = 6.46x10⁻⁵ = [B⁻] [H⁺] / [BH]
If 20.0% is B⁻, 80.0% is BH, replacing:
6.46x10⁻⁵ = [20.0%] [H⁺] / [80.0%]
1.615x10⁻⁵ = [H⁺]
As pH = -log [H⁺]
pH = 4.79The mass of 900. atoms of sodium(Na)
Answer:
3.44 × 10⁻²⁰ g Na
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:
Step 1: Define
900 atoms Na
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of Na - 22.99 g/mol
Step 3: Convert
[tex]900 \ atoms \ Na(\frac{1 \ mol \ Na}{6.022 \cdot 10^{23} \ atoms \ Na} )(\frac{22.99 \ g \ Na}{1 \ mol \ Na} )[/tex] = 3.4359 × 10⁻²⁰ g Na
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
3.4359 × 10⁻²⁰ g Na ≈ 3.44 × 10⁻²⁰ g Na
Easy Mole Conversion:
How many grams are in 2.00 moles of cobalt (I) hydroxide?
Answer:
Mass = 185.896 g
Explanation:
Given data:
Mass in gram = ?
Number of moles = 2.00 mol
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of cobalt (I) hydroxide =92.948 g/mol
by putting the values,
2.00 mol = Mass/92.948 g/mol
Mass = 2.00 mol × 92.948 g/mol
Mass = 185.896 g