Answer:
3.41 g
Explanation:
A chemist adds 260.0 mL of a 0.0832M potassium permanganate solution to a reaction flask. Calculate the mass in grams of potassium permanganate the chemist has added to the flask. Round your answer to 3 significant digits.
Step 1: Given data
Volume of the solution (V): 260.0 mL (0.2600 L)
Concentration of the solution (C): 0.0832 M (0.0832 mol/L)
Step 2: Calculate the moles (n) of potassium permanganate added
We will use the following expression.
n = C × V
n = 0.0832 mol/L × 0.2600 L = 0.0216 mol
Step 3: Calculate the mass corresponding to 0.0216 moles of potassium permanganate
The molar mass of potassium permanganate is 158.03 g/mol.
0.0216 mol × 158.03 g/mol = 3.41 g
What do scientists think is the
reason the mollusks have been so
successful through time?
B
Answer: Body plans change as new challenges arise.
Explanation:
The mollusks are the invertebrate animals. They live marine environment. They live in shallow waters. They have been found in variety of marine habitats so this indicates their adaptiveness to different conditions. They have body plan that comprises of shell, mantle, radula and muscular foot that helps in survival and adaptation in different conditions. The shell and mantle are hard structures which protect these animals from predators and also help them to camouflage. Also the muscular foot helps in locomotion. Radula helps in feeding. Oysters, snails are some examples of mollusks.
The oldest known flower lived 120, million years ago. Is that a measured or exact number?
Answer:
measured
Explanation:
no way can they pin point exactly when something lived when its in the millions
A 0.4647-g sample of a compound known to contain only carbon, hydrogen, and oxygen was burned in oxygen to yield 0.8635 g of CO2 and 0.1767 g of H2O. What is the empirical formula of the compound?
Answer: The empirical formula is [tex]C_3H_3O_2[/tex].
Explanation:
The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:
[tex]C_xH_yO_z+O_2\rightarrow CO_2+H_2O[/tex]
where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.
We are given:
Mass of [tex]CO_2[/tex] = 0.8635
Mass of [tex]H_2O[/tex]= 0.1767 g
Molar mass of carbon dioxide = 44 g/mol
Molar mass of water = 18 g/mol
For calculating the mass of carbon:
In 44g of carbon dioxide, 12 g of carbon is contained.
So, in 0.8635 g of carbon dioxide, =[tex]\frac{12}{44}\times 0.8635=0.2355g[/tex] of carbon will be contained.
For calculating the mass of hydrogen:
In 18g of water, 2 g of hydrogen is contained.
So, in 0.1767 g of water, =[tex]\frac{2}{18}\times 0.1767=0.0196g[/tex] of hydrogen will be contained.
Mass of oxygen in the compound = (0.4647) - (0.2355+0.0196) = 0.2096 g
Mass of C = 0.2355 g
Mass of H = 0.0196 g
Step 1 : convert given masses into moles.
Moles of C =[tex] \frac{\text{ given mass of C}}{\text{ molar mass of C}}= \frac{0.2355g}{12g/mole}=0.0196moles[/tex]
Moles of H=[tex]\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{0.0196g}{1g/mole}=0.0196moles[/tex]
Moles of O=[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{0.2096g}{16g/mole}=0.0131moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C =[tex]\frac{0.0196}{0.0131}=1.5[/tex]
For H =[tex]\frac{0.0196}{0.0131}=1.5[/tex]
For O = [tex]\frac{0.0131}{0.0131}=1[/tex]
The ratio of C : H: O = 1.5 : 1 .5 : 1
Converting to simple whole number ratio:
The ratio of C : H: O = 3 : 3: 2
Hence the empirical formula is [tex]C_3H_3O_2[/tex].
How do you know when to put a positive or negative exponent?
Answer:
If a negative number is raised to an even power, the result will be positive. If a negative number is raised to an odd power, the result will be negative. The negative number must be enclosed by parentheses to have the exponent apply to the negative term.
Explanation:
is a planar carbon "backbone" possible for propane? Explain.
Is a planar carbon "backbone" possible for cyclopropane? Explain.
Answer:
Cyclopropane has a planar carbon back bone while propane does not
Explanation:
We have to recognize that in straight chain saturated organic compounds, carbon atoms have a tetrahedral geometry. Each carbon atom is bonded to four other atoms.
However, carbon atoms in cyclic compounds are also sp3 hybridized with each carbon bonded to only four other atoms but the ring system is highly strained.
Cyclopropane is a necessarily planar molecule with a bond angle that is far less than the expected tetrahedral bond angle due to strain in the molecule. Hence, the carbon atoms may have have a "planar backbone".
94.9 grams of Br is equivalent to how many moles of Br?
Answer:
The answer is 79.904.
Explanation:
We assume you are converting between grams Br and mole.
You can view more details on each measurement unit:
molecular weight of Br or mol
The SI base unit for amount of substance is the mole.
1 grams Br is equal to 0.012515018021626 mole.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between grams Br and mole.
Type in your own numbers in the form to convert the units!
give 5 stars rn
Describe briefly how you will determine the relative density of kerosene
Explanation:
First determine the weight of the density bottle(A1) when it's empty.
Then fill it with the liquid you want to determine the density.
Then determine the weight of the bottle with the liquid(A2).
Then the weight of the liquid is equal to (A2 - A1)
You already know the volume of the bottle.
Apply them to density = weight/volume
Make sure to mention the temperature you measured it because density varies from one temperature to another.
someone help me pls ada
carbon dioxide is in a steel tank at 20 degrees celsius and 10 liters. what is the volume on the gas when the tank is heated to 100 degrees celsius?
Answer:
12.73 L
Explanation:
Given that,
Initial temperature, [tex]T_i=20^{\circ}=20+273=293\ K[/tex]
Initial volume, [tex]V_i=10\ L[/tex]
We need to find the volume on the gas when the tank is heated to 100 degrees celsius or 373 K.
We know that volume is directly proportional to the temperature of the gas. Using above relation,
[tex]\dfrac{V_i}{T_i}=\dfrac{V_f}{T_f}\\\\V_f=\dfrac{V_iT_f}{T_i}[/tex]
Putting all the values,
[tex]V_f=\dfrac{10\times 373}{293}\\\\V_f=12.73\ L[/tex]
So, the final volume of the gas is 12.73 L.
At what step of glycolysis one NADH+ H+ is formed?
Answer:
During Glycolysis, there is one step where NADH + H+ is formed from NAD+ O F-6-P - F- 1,6-BP O PGAL – 1,3-BPGA O 2-PGA - PEP O 3-PGA → 2-PGA.
Anyone Can help me this question ♂️ please ?
Answer:
54.66 liters
Explanation:
First of all, remember this. 1 mole equals 22.4 liters.
Second of all, to show your work use dimensional analysis.
Write 2.44 moles and then put moles on the bottom and liters on top.
2.44 moles of O * 22.4 liters / 1 mol of O
Moles will cancel out.
2.44 x 22.4 = 54.656
Usually I would have used sig figs. But the question said to round your answer to two digits after the decimal point.
54.656 rounds to the hundreths place.
So 54.656 = 54.66
All in all, the final answer is 54.66 liters(don't forget the units).
Hope it helped!
Which of the following elements is most reactive?
A.LI
B.Ne
C.K
D.Au
E.Cs
Answer:
E
Explanation:
Anything going down Column 1 is going to be more reactive than anything else.
So the only contenders that are in column 1 are Li and Cs. The most reactive ones are the ones going down.
Cs is at the bottom of column 1. The answer is E
Draw a Lewis structure of the molecule that matches the description below. All non- H atoms should have full octets, and all formal charges should be zero. Unless you're told otherwise, assume there are no rings in the molecule.
Description: The molecule is composed of
2 C 's, 5 H 's, and 1 N and it contains a C - C double bond.
Answer:
See attached picture.
Explanation:
Hello!
In this case, according to the given instructions, on the attached picture you will find the required Lewis structure, whereas there is a double bond between the two carbon atoms, and one of those is bonded to the nitrogen; moreover the terminal carbon has two out of five hydrogen atoms, the middle carbon, one out of five and the nitrogen atom has two out of five hydrogen atoms; therefore the molecule would be ethenamine.
Best regards!
Select the correct balanced equation for the single displacement reaction of bromine and potassium iodine.
Br + Kl -> KBr +1
Answer:
D
D...............DDDDDDD
Answer: D
Explanation:
The answer is D as it is the only correctly balanced equation.
Construct an explanation using Newton's Laws of Motion to describe the effects of balanced and unbalanced forces on the motion of an object.
Answer:
The manner in which objects will move is determined by the answer to this question. Unbalanced forces will cause objects to change their state of motion
Explanation:
Since these two forces are of equal magnitude and in opposite directions, they balance each other.
Answer:
balance force are those force whose resultant force is zero and unbalanced force are those whose resultant are non zero
How many sulfur atoms are in 5 SF6 ?
Answer:
The molecular formula for sulfur hexafluoride is SF6 S F 6 , in which there is 1 sulfur atom and 6 fluorine atoms.
Explanation:
hope this helps
In table below, there are descriptions of an experiment on samples of three different chemical compounds. Decide whether the compound is ionic or molecular, if you can. If there is not enough information to decide, choose can't decide in the third column.
compound description ionic or molecular
1 Compound 1 is a light gray solid made of
overlapping hexagonal crystals. When heated gently it
starts to soften and develop an unpleasant smell about
50 °C. above room temperature.
2 Compound 2 is a dull white smooth solid which does not
conduct electricity. Applying an ordinary laboratory burner
to the material only makes the substance hot, it does not
otherwise change. In fact, the substance can't be melted
or even softed by any ordinary laboratory equipment.
3 Compound 3 is a clear liquid with a strong pleasantly
fruity smell. If cooled it freezes at about -10 °C. In the
solid state it does not conduct electricity.
Answer:
Compound 1 is molecular
Compound 2 is ionic
Compound 3 can't really be decided
Explanation:
A molecular substance does not conduct electricity, has very low melting and boiling points and is held together by very weak intermolecular forces.
An ionic substance conducts electricity in solution or in molten state but never in the pure solid state, has a high melting and boiling point and has a dull appearance most times.
Compounds 1 shows the properties of molecular substances hence it are designated as such.
On the other hand, compound 2 shows the properties of an ionic substance and is also designated as such.
We can't really decide on compound 3 because it shows some properties of ionic substances and some properties of molecular substances.
Identify which element is the least malleable: potassium, calcium, scandium, or titanium
A student working in the laboratory produces 6.81 grams of calcium oxide, CaO, from 20.7 grams of calcium
carbonate, CaCO3, according to the reaction CaCO3 → CaO + CO2. Calculate the theoretical yield and
the percent yield for the reaction. Show and/or explain your work.
Answer:
A. Theoretical yield of CaO is 11.59 g
B. Percentage yield of CaO = 58.76%
Explanation:
The following data were obtained from the question:
Mass of CaCO₃ = 20.7 g
Actual yield of CaO = 6.81 g
Theoretical yield of CaO =?
Percentage yield of CaO =?
The equation for the reaction is given below:
CaCO₃ —> CaO + CO₂
Next, we shall determine the mass of CaCO₃ that decomposed and the mass of CaO produced from the balanced equation. This can be obtained as follow:
Molar mass of CaCO₃ = 40 + 12 + (3×16)
= 40 + 12 + 48
= 100 g/mol
Mass of CaCO₃ from the balanced equation = 1 × 100 = 100 g
Molar mass of CaO = 40 + 16 = 56 g/mol
Mass of CaO from the balanced equation = 1 × 56 = 56 g
SUMMARY:
From the balanced equation above,
100 g of CaCO₃ decomposed to produce 56 g of CaO.
A. Determination of the theoretical yield of CaO.
From the balanced equation above,
100 g of CaCO₃ decomposed to produce 56 g of CaO.
Therefore, 20.7 g of CaCO₃ will decompose to produce =
(20.7 × 56)/100 = 11.59 g of CaO.
Thus, the theoretical yield of CaO is 11.59 g
B. Determination of the percentage yield.
Actual yield of CaO = 6.81 g
Theoretical yield of CaO = 11.59 g
Percentage yield of CaO =?
Percentage yield = Actual yield /Theoretical yield × 100
Percentage yield = 6.81/11.59 × 100
Percentage yield of CaO = 58.76%
write few lines about luis braille
Answer:
Louis braille was a french educator and inventor of a sytem of reading and writing for use use by the blind or visually impaired . his system remains virtually unchanged to this day and is know worldwide simply as braille
The wormwood plant is known for having leaves that taste bitter and have a strong odor. What advantage would these qualities give the
wormwood plant?
A. It would be more likely to repel other plants.
B. It would be less likely to be grown for use by humans.
C. It would be less likely to be eaten by insects.
D. It would be more likely to attract birds.
Answer:
C. It would be less likely to be eaten by insects.
Explanation:
The bitter taste and strong odor of the wormwood plant would repel the insects from eating the plant.
This is an adaptation by the tree to prevent is from being destroyed by the insect that would feed on its leaves. The bitter taste would not be edible for the insect to feed on. Also, the strong odor will not be attractive for the insects. So, the tree is well adapted to survive any insect invasion.Suppose your metal sample is hammered into the shape of a thin coin with a diameter of 8.62 cm. Determine the thickness (in mm) of this metal sheet. Use the measured metal mass and true denisty of your metal for this calculation.
measured metal mass: 83.956 g
true density: 8.90 g/cm3
Answer:
The thickness of the metal sheet is 0.162 centimeters.
Explanation:
If mass within the coin is uniformly distributed, then the density ([tex]\rho[/tex]), measured in grams per cubic centimeter, can be represented by the following formula:
[tex]\rho = \frac{m}{\frac{\pi}{4}\cdot D^{2}\cdot z }[/tex] (1)
Where:
[tex]m[/tex] - Mass, measured in grams.
[tex]D[/tex] - Diameter, measured in centimeters.
[tex]z[/tex] - Thickness, measured in centimeters.
If we know that [tex]m = 83.956\,g[/tex], [tex]D = 8.62\,cm[/tex] and [tex]\rho = 8.90\,\frac{g}{cm^{3}}[/tex], then the thickness of the coin is:
[tex]z = \frac{m}{\frac{\pi}{4}\cdot D^{2}\cdot \rho }[/tex]
[tex]z = \frac{83.956\,g}{\frac{\pi}{4}\cdot (8.62\,cm)^{2}\cdot \left(8.90\,\frac{g}{cm^{3}} \right) }[/tex]
[tex]z = 0.162\,cm[/tex]
The thickness of the metal sheet is 0.162 centimeters.
If you put an iron nail into a beaker of copper chloride, you will begin to see a reddish precipitate forming on the nail. In this reaction, iron replaces copper in the solution and copper falls out of the solution as a metal.
The balanced equation is Fe+CuCl -> FeCl2+Cu
If you start out with one mole of your limiting reactant (Fe), how many grams of copper can you expect to produce through this reaction?
Answer:
63.6g
Explanation:
The reaction expression is given as:
Fe + CuCl₂ → FeCl₂ + Cu
Given:
Number of moles of Fe = 1 mole
Unknown:
Mass of copper that would be produced;
Solution:
From the balanced reaction expression:
1 mole of Fe will produce 1 mole of Cu;
So;
Mass of Cu produced = number of moles x molar mass
Mass of Cu = 1 mole x 63.6g/mol = 63.6g
Which of the statements about liquids and gases are true?
Both liquids and gases have a definite volume.
O The particles in liquids and gases can move past one another
freely
Both liquids and gases have a definite shape.
Neither liquids nor gases have a definite shape.
Which of the statements about liquids and gases are true?
Answer:The particles in liquids and gases can move past one another freely.
#CARRYONLEARNING #STUDYWELLWhich of the statements about liquids and gases are true?
Choosing:Both liquids and gases have a definite volume.
The particles in liquids and gases can move past one another freely
Both liquids and gases have a definite shape.
Neither liquids nor gases have a definite shape.
Answer:The particles in liquids and gases can move past one another freely.
#READINGHELPSWITHLEARNING #CARRYONLEARNING #STUDYWELLA gas mixture in a rigid container has a total pressure of 2.5 atm. One gas, lets call it X, has 0.85 moles and accounts for 1.2 atm of pressure. What is the mole fraction of the other gases (all gases that are not X) in the container?
The mole fraction of the other gases : 0.52
Further explanationGiven
P tot = 2.5 atm
P x = 1.2 atm, n = 0.85 moles
Required
mole fraction
Solution
P tot = P gas X + P other gases
mol fraction = mol x : mol total
P gas X = mol fraction gas X x P total
1.2 atm = mol fraction gas X x 2.5 atm
mol fraction gas X = 0.48
mol fractionof the other gases = 1 - 0.48 = 0.52
Or we can use
P other gases = 2.5 - 1.2 = 1.3 atm
mol fraction the other gases = 1.3 : 2.5 = 0.52
6. Three of these terms belong together. Which one doesn't belong?
A) nucleus
B) cytoplasm
C) cell wall
D) cell membrane
Explain why the one you chose doesn't belong with the other three?
Answer:
i am 50/50 at the memoent but i have a feeling it is the cytoplasm as it isnt a cell like the others. Hope this helps :(
Explanation:
The currently accepted model of the atom includes an electron cloud.
A. True
B. False
Answer:
True
Explanation:
Answer: True
Explanation:
What is the mass, in grams, of a pure iron cube that has a volume of 3.80 cm?
Answer:
2.66 g of Fe, can be obtained from the reaction
Explanation:
Let's think the reaction:
2Fe₂O₃ + 6CO → 4Fe + 6CO₂
Ratio is 2:4, so If i have x moles of iron (III) oxide, I will produce the double of moles of Fe.
Mass / Molar mass = Mol
3.80 g / 159.7 g/m = 0.0237 moles
0.0237 moles . 2 = 0.0475 moles
Molar mass Fe = 55.85 g/m
Mol . Molar mass = Mass → 0.0475 m . 55.85 g/m = 2.66 grams
Explanation:
Sodium chlorite decomposes into salt and oxygen gas. What is the correct balanced decomposition reaction.
NaClO3 -> NaCl + O2
Answer:
i think it would be c
Explanation:
sorry if it is wrong
Answer:
2NaClO₃ -> 2NaCl + 3O₂
Explanation:
The number of atoms in the reactants has to equal the number of atoms in the products.
Hope that helps.
Given the molecular formula, C2H8N, write the empirical formula.
Answer:
C2H8N
Explanation:
it wont change since there is no common factor between the 2:8:1 which will give us a whole number so it stays the same