Menthol is a crystalline substance with a peppermint taste and odor. When 0.533 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 2.84 ∘C. Look up the freezing point and f constant for cyclohexane in the Colligative Constants table. Calculate the molar mass of menthol.
Answer: The molar mass of menthol is 156.15 g/mol
Explanation:
Depression in freezing point is given by:
[tex]\Delta T_f=K_f\times m[/tex]
[tex]\Delta T_f=T_f^0-T_f=2.84^0C[/tex] = Depression in freezing point
[tex]K_f[/tex] = freezing point constant = [tex]20.8^0C/m[/tex]
m= molality
[tex]\Delta T_f=K_f\times \frac{\text{mass of solute}}{\text{molar mass of solute}\times \text{weight of solvent in kg}}[/tex]
Weight of solvent (cyclohexane)= 25.0 g = 0.025 kg
Molar mass of solute (menthol) = ?
Mass of solute (menthol) = 0.533 g
[tex]2.84^0C=20.8\times \frac{0.533}{xg/mol\times 0.025}[/tex]
[tex]x=156.15g/mol[/tex]
The molar mass of menthol is 156.15 g/mol
I need help with this!
Answer:
2.68 cm^3
Explanation:
Density= Mass/Volume
so...
8.96 g/cm^3 = 24.01 g/ V
and then u solve so it would be 2.68 cm ^3
((:
number of balance electrons of a non ionized oxygen atom
How many atoms of Kr (Krypton) are in a balloon that contains 2.00 mol of Kr? (4)
Answer:
[tex]atoms= 1.204x10^{24}atoms[/tex]
Explanation:
Hello!
In this case, according to the Avogadro's number, it is possible to compute the atoms of Kr in 2.00 moles as shown below:
[tex]atoms=2.00mol*\frac{6.022x10^{23}atoms}{1mol} \\\\atoms= 1.204x10^{24}atoms[/tex]
Best regards!
how might the biodiversity of a mowed lawn compare to that of huge weedy field?
Answer: The mowed lawn is the one from where the grasses are removed by using the machines or tools.
Explanation:
The mowed lawn is expected to have low number of species as the grasses may be few or scanty thus can support the population of few species like insects, mice, birds, and small number of grazing animals. On the other hand the weedy field can be hub of insects, reptiles like snakes, small mammals, and large mammals. Large weed field can provide food, and habitat to the large number of species. This will support the increase in biodiversity as compared to the mowed lawn.
There are four conditions an atom needs to meet to participate in hydrogen bonding. It needs to be_______ enough not to bump into other atoms when approaching the 1s orbital of the hydrogen, it needs to carry at least one________ atom, it needs to be_________enough to create a delta on the connected hydrogen, and it needs to have at least one________.
Answer:
The conditions are
1) Small enough
2) Electronegative atom
3) highly electronegative
4) lone pair of electrons
The correct statement therefore is
It needs to be small enough not to bump into other atoms when approaching the 1s orbital of the hydrogen, it needs to carry at least one electronegative atom, it needs to be highly electronegative enough to create a delta on the connected hydrogen, and it needs to have at least one lone pair of electrons.
Explanation:
Hydrogen bonding is a type of intermolecular bond that occurs between the partial positive charge (delta) on a hydrogen atom bonded to a small highly electronegative element (like nitrogen, oxygen or fluorine) and the free electrons on another electronegative element of another molecule.
The hydrogen atom with the partial positive charge (delta) is known as the hydrogen bond donor, while the electronegative element, carrying lone electrons is called the hydrogen bond acceptor.
Let's take a deeper look at these terms:
1) Hydrogen bond donor
Using water (H₂O) as an example, the high electronegativity of the oxygen atom covalently bonded to the hydrogen atom draws the lone electron in the 1s orbital of the hydrogen atom, creating a partial positive charge (d⁺) on the hydrogen atom. This is what happens within one water molecule
2) Hydrogen bond acceptor
When two or more molecules of water interact, the partial positive charge (d⁺) on the hydrogen atom of one molecule, is attracted to the valence or free electrons on the oxygen atom of a nearby molecule of water thus creating a dipole-dipole intermolecular bond known as a hydrogen bond.
For the hydrogen bond to be effective, the electronegative atom bonded to the hydrogen acting as the hydrogen bond donor in the first water molecule needs to be small enough so as not to disrupt the 1s orbital of the hydrogen atom. The smaller the size of the electronegative atom, the stronger the partial negative charge created on the hydrogen atom.
The valence or free pair of electrons on the electronegative (oxygen) atom of the second molecule of water (hydrogen bond acceptor) is what attracts the partial positive charge on the hydrogen atom to create the hydrogen bond
The reform reaction between steam and gaseous methane (CH4) produces "synthesis gas," a mixture of carbon monoxide gas and dihydrogen gas. Synthesis gas is one of the most widely used industrial chemicals, and is the major industrial source of hydrogen. Suppose a chemical engineer studying a new catalyst for the reform reaction finds that 924. liters per second of methane are consumed when the reaction is run at 261.°C and 0.96atm. Calculate the rate at which dihydrogen is being produced.
Answer:
The answer is "[tex]= 0.078 \ kg \ H_2[/tex]".
Explanation:
calculating the moles in [tex]CH_4 =\frac{PV}{RT}[/tex]
[tex]=\frac{(0.58 \ atm) \times (923 \ L) }{ (0.0821 \frac{L \cdot atm}{K \cdot mol})(232^{\circ} C +273)}\\\\=\frac{(535.34 \ atm \cdot \ L) }{ (0.0821 \frac{L \cdot atm}{K \cdot mol})(505)K}\\\\=\frac{(535.34 \ atm \cdot \ L) }{ (41.4605 \frac{L \cdot atm}{mol})}\\\\= 12.9 \ mol[/tex]
Eqution:
[tex]CH_4 +H_2O \to 3H_2+ CO \ (g)[/tex]
Calculating the amount of [tex]H_2[/tex] produced:
[tex]= 12.9 \ mol CH_4 \times \frac{3 \ mol \ H_2 }{1 \ mol \ CH_4}\times \frac{2.016 g H_2}{1 \ mol \ H_2}\\\\= 78 \ g \ H_2 \\\\= 0.078 \ kg \ H_2[/tex]
So, the amount of dihydrogen produced = [tex]0.078 \frac{kg}{s}[/tex]
Vitamin C is a covalent compound with the molecular
formula C6H8O6. The recommended daily dietary
allowance of vitamin C for children aged 4-8 years is
0.000142mol. What is the mass of this allowance in grams?
The mass allowance of Vitamin C for children aged 4-8 years is equal to 0.025 grams.
What is a mole?A mole can be defined as a standard unit that can be utilized to evaluate the number of entities such as atoms, molecules, ions, or other particular particles in a particular amount of the substance.
The number of elementary entities present in one mole of any chemical substance was found to be equal to 6.023 × 10²³ which is also known as the Avogadro number.
Given, the number of moles of vitamin C = 0.000142 moles
Given, the molecular formula of Vitamin C is C₆H₈O₆.
The mass of one mole of C₆H₈O₆ = 176 g
One mole of Vitamin C has mass = 176 g
0.000142 mol of Vitamin C has mass = 0.000142×176 = 0.025 g
Therefore, the mass of 0.000142 mol of Vitamin C is 0.025 g.
Learn more about the mole, here:
brainly.com/question/26416088
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5) The stability of an atom is determined by
Re 1) P+n
2)P-n
3) P/N
4) N/P
Answer:
the answer p+n
Explanation:
Calculate the [H+]
and pH of a 0.000295 M
butanoic acid solution. Keep in mind that the a
of butanoic acid is 1.52×10−5
[H⁺]=6.696 x 10⁻⁵
pH = 4.174
Further explanationGiven
The concentration of 0.000295 M (2.95 x 10⁻⁴ M) butanoic acid solution
Required
the [H+] and pH
Solution
Butanoic acid is the carboxylic acid group. Carboxylic acids are weak acids
For weak acid :
[tex]\tt [H^+]=\sqrt{Ka.M}[/tex]
Input the value :
[H⁺]=√1.52 x 10⁻⁵ x 2.95 x 10⁻⁴
[H⁺]=6.696 x 10⁻⁵
pH = - log [H⁺]
pH = - log 6.696 x 10⁻⁵
pH = 5 - log 6.696
pH = 4.174
Use the atom builder interactive to identify each nucleus. Two protons represented as purple spheres and one neutron represented as a white sphere.Two protons represented as purple spheres and four neutrons represented as white spheres.Four protons represented as purple spheres and three neutrons represented as white spheres. One proton represented as a purple sphere and two neutrons represented as white spheres.Four protons represented as purple spheres and two neutrons represented as white spheres.Three protons represented as purple spheres and four neutrons represented as white spheres. Answer Bank
Answer:
[tex]\frac{3}{2}He[/tex]
[tex]\frac{6}{2} He[/tex]
[tex]\frac{7}{4}Be[/tex]
[tex]\frac{3}{1} H[/tex]
[tex]\frac{6}{4}Be[/tex]
[tex]\frac{7}{3} Li[/tex]
Explanation:
In the first nucleus we are told that there are two protons and one neutron. Let us remember that the mass number = number of protons + number of neutrons.
This implies that, for the first specie the mass number is 3, for the second specie the mass number is 6 and the third specie has a mass number of 7 and so on. The mass number is indicated as a superscript.
The atomic number is the number of protons in the nucleus of the atom and helps us to identify the atom. It is always written as a subscript as shown.
HELPPPP PLZ
Using an applied force to move an object in the direction of the force is...
potential energy
the scientific definition of work
none of these
the scientific definition of power
Answer:
the scientific definition of work
Explanation:
In physics, work is defined as the use of force to move an object. For work to be done, the force must be applied in the same direction that the object moves.
I hope it helps! ^^
☁️☁️☁️☁️☁️☁️☁️
Which of the following statements is false?
a. This class discussed four physical states of matter
b. An atom is the smallest particle of an element that still contains properties of the original element.
c. Gases can be colorless or colored
d. Mass is the measure of the earth’s gravitational attraction of a body
e. A pure substance has a fixed composition.
Answer:
d. Mass is the measure of the earth’s gravitational attraction of a body
This is FALSE. Mass is the measure of matter than an object contains.
Explanation:
b. An atom is the smallest particle of an element that still contains properties of the original element.
This is True
c. Gases can be colorless or colored
This is True
d. Mass is the measure of the earth’s gravitational attraction of a body
This is FALSE. Mass is the measure of matter than an object contains.
e. A pure substance has a fixed composition.
This is True.
Gizmo Warm-up In a chemical reaction, reactants interact to form products. This process is summarized by a chemical equation. In the Balancing Chemical Equations Gizmo, look at the floating molecules below the initial reaction: H2 O2 ---> H2O. How many atoms are in a hydrogen molecule (H2)
Answer:
There are two atoms in one hydrogen molecule.
Explanation:
Hello!
In this case, when going over chemical reactions, we need to realize about the amount of atoms of each element; thus, according to the given chemical reaction by which water is formed:
[tex]H_2+O_2\rightarrow H_2O[/tex]
It is seen there are two hydrogen atoms in the hydrogen molecule, two in oxygen and two hydrogen atoms and one oxygen atom in water; however, these reactions must be balanced according to the law of conservation of mass:
[tex]2H_2+O_2\rightarrow 2H_2O[/tex]
Which means we have two hydrogen molecules with two atoms each, one oxygen molecule with two atoms and two water molecules with two hydrogen atoms and one oxygen atom each.
Best regards!
Convert 5.802 g/cm^3 to Kg/L
Answer:
5.80200 Kg / L
Explanation:
What is the mass of 2.14 mol CaCl2?
Answer:
237.5 grams CaCl2
Explanation:
Use the periodic table to calculate the mass of CaCl2
40.078+(35.45*2)=110.97800
Convert: 2.14 mol CaCl2 * 110.98g CaCl2/1 mol CaCl2 = 237.4972 g
Liquid octane CH3CH26CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 2.3 g of octane is mixed with 12.4 g of oxygen. Calculate the minimum mass of octane that could be left over by the chemical reaction. Round your answer to 2 significant digits.
Answer: Octane will be used completely.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of octane}=\frac{2.3g}{114g/mol}=0.0202moles[/tex]
[tex]\text{Moles of oxygen}=\frac{12.4g}{32g/mol}=0.388moles[/tex]
The balanced chemical reaction will be
[tex]2C_8H_{18}+25O_2(g)\rightarrow 16CO_2(g)+18H_2O(g)[/tex]
According to stoichiometry :
2 moles of octane require = 25 moles of [tex]O_2[/tex]
Thus 0.0202 moles of octane will require=[tex]\frac{25}{2}\times 0.0202=0.2525moles[/tex] of [tex]O_2[/tex]
Thus octane is the limiting reagent as it limits the formation of product and [tex]O_2[/tex] is the excess reagent.
Thus octane will be used completely.
What is the mass in grams of 1.00 x 10 24 atoms of Mn?
a)91.3 g
b) 123.4 g
c) 1.66 g
d) 166 g
91.2 g Mn
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 1.00 × 10²⁴ atoms Mn
Step 2: Identify Conversions
Avogadro's Numer
[PT] Molar Mass of Mn - 54.94 g/mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 1.00 \cdot 10^{24} \ atoms \ Mn(\frac{1 \ mol \ Mn}{6.022 \cdot 10^{23} \ atoms \ Mn})(\frac{54.94 \ g \ Mn}{1 \ mol \ Mn})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 91.2321 \ g \ Mn[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
91.2321 g Mn ≈ 91.2 g Mn
Which one of the following statements best describes electronegativity in atoms?
A) Electronegativity is what happens when an atom gains an electron to become an anion.
B) Electronegativity is the attraction an element's nucleus has for the electrons in a chemical bond
C) Electronegativity is the energy lost when an atom gains an electron
D) Electronegativity is the energy absorbed when an atom loses an electron
Answer: B) Electronegativity is the attraction an element's nucleus has for the electrons in a chemical bond
Explanation:
Electronegativity is defined as the property of an element to attract a shared pair of electron towards itself.
When the size of an atom decreases as we move across the period, as the electrons get added to the same shell and the nuclear charge keeps on increasing. Thus the electrons get more tightly held by the nucleus.
As, the size of an element decreases, the valence electrons come near to the nucleus. So, the attraction between the nucleus and the shared pair of electrons increases and thus the electronegativity increases.
A catalyst will
a) Increase the reaction rate
b) Move the equilibrium to the right
c) Be consumed by the reaction
d) Increase the activation energy
Answer:
increase the chemical rate
How many grams of sulfur must be burned to give 100.0 g of So2
Answer:
50 g of S are needed
Explanation:
To star this, we begin from the reaction:
S(s) + O₂ (g) → SO₂ (g)
If we burn 1 mol of sulfur with 1 mol of oxygen, we can produce 1 mol of sulfur dioxide. In conclussion, ratio is 1:1.
According to stoichiometry, we can determine the moles of sulfur dioxide produced.
100 g. 1mol / 64.06g = 1.56 moles
This 1.56 moles were orginated by the same amount of S, according to stoichiometry.
Let's convert the moles to mass
1.56 mol . 32.06g / mol = 50 g
Baking soda and vinegar questions
Binary compounds are formed by ............... ............... elements.
Answer: i think its A diatomic compound..
Explanation: hope i helped! sorry if im wrong!
For the reaction 2Fe+o2 -->Feo how many grams of iron(ll) oxide are produced from 479.6 grams of iron in an excess of oxygen (Fe=56gmol, O=16g mol)
Mass of iron(ll) oxide= 616.608 g
Further explanationGiven
Reaction
2Fe+O2 -->2FeO
479.6 grams of iron
Required
mass of iron(ll) oxide
Solution
mol of iron :
= mass : Ar Fe
= 479.6 g : 56 g/mol
= 8.564
From the equation, mol FeO :
= 2/2 x mol Fe
= 2/2 x 8.564
= 8.564 moles
Mass of iron(ll) oxide :
= mol x MW
= 8.564 x 72 g/mol
= 616.608 g
Consider the following reaction where K. = 9.52 10 2 at 350 K.
CH,(g) + CC14(2)—2CH2Cl2(g)
A reaction mixture was found to contain 2.21*10-2 moles of CH4(E), 3.8710-2 moles of CC1,(g) and 1.06-10-2 moles of CH,C12(2), in
a 1.00 liter container
Is the reaction at equilibrium?
If not, what direction must it run in order to reach equilibrium?
The reaction quotient, Qc equals
The reaction
A. must run in the forward direction to reach equilibrium
B. must run in the reverse direction to reach equilibrium
C. is at equilibrium
Answer:
The correct answer is A :))
What is the molecular formula of the molecule that has an empirical formula of C2H40 and a molar mass of 176.21 g/mol?
Type your answer using the following format:
CuCl2 for CuCl2.
Answer:
C8H16O4
Explanation:
C2H4O= 24+4+16
44
n=molar mass/empirical formula
n=176.21/44
=4
Therefore
Molar Formula= (C2H4O)4=C8H16O4
The mass fractions of a mixture of gases are 15 percent nitrogen, 5 percent helium, 60 percent methane, and 20 percent ethane with a total mixture molecular weight of 16.12 kg/kmole. Determine the mole fraction of each constituent, the partial pressure of each constituent when the mixture pressure is 1200 kPa and the apparent specific heats of the mixture when the mixture is at room temperature.
Answer:
Explanation:
mass fraction N₂ : He : CH₄ : C₂H₆ : : 15 : 5 : 60 : 20
mole fraction N₂ : He : CH₄ : C₂H₆ : : 15/28 : 5/4 : 60/16 : 20/30
mole fraction N₂ : He : CH₄ : C₂H₆ : : .5357 : 1.25 : 3.75 : .67
Total mole fractions = .5357 + 1.25 + 3.75 + 0.67 = 6.2057
mole fraction of N₂ = .5357 / 6.2057 = .0877
mole fraction of He = 1.25 / 6.2057 = .20
mole fraction of CH₄ = 3.75 / 6.2057 = .6043
mole fraction of C₂H₆ = .67 / 6.2057 = .108
Partial pressure = total pressure x mole fraction
Partial pressure of N₂ = 1200 kPa x .0877 = 105.24 kPa
Partial pressure of He = 1200 kPa x .20 = 240 kPa
Partial pressure of CH₄ = 1200 kPa x .6043 = 725.16 kPa
Partial pressure of C₂H₆ = 1200 kPa x .108 = 129.6 kPa
Name each of the following organic molecules. 
A molten sample of 1.00kg of iron with a specific heat of 0.385J/g.K at 1000.K is immersed in a sample of water. If the water absorbs 270 kJ of heat what is the final temperature of the iron?
I need all the process.
Answer:
298. 7 K.
Explanation:
Hello!
In this case, since equation we use to compute the heat in a cooling or heating process is:
[tex]Q=mC(T_f-T_i)[/tex]
Whereas we are given the heat, mass, specific heat and initial temperature. Thus, we infer that we need to solve for the final temperature just as shown below:
[tex]T_f=T_i+\frac{Q}{mC}\\\\T_f=1000 K+\frac{-270000J}{1000g*0.385\frac{J}{g*K} } \\\\T_f=298.7 K[/tex]
It is important to notice that the iron release heat as water absorbs it, that is why it is taken negative.
Best regards!
If two reactant molecules collide with each other what two reasons might they not combine ?