Answer:
12 g
Explanation:
From the question given above, the following data were:
Number of atoms = 6.02×10²³ atoms
Mass of ₆C¹² =?
From Avogadro's hypothesis,
1 mole of any substance contains 6.02×10²³ atoms. This implies that 1 mole of ₆C¹² also contains 6.02×10²³ atoms i.e
1 mole of ₆C¹² = 6.02×10²³ atoms
Recall
From the period,
1 mole of ₆C¹² = 12 g
Thus,
12 g of ₆C¹² = 6.02×10²³ atoms
Therefore, 12 g of ₆C¹² contains 6.02×10²³ atoms
PLZ HELP which ia an example of a scientist using a physical model to describe a river
A. the scientists thinks of a river like a flow of electrons
B. the scientists builds a model of the river using plastic and a hose
C. the scientists writes an equation that describes the flooding of the river
D. the scientists uses a computer to predict how much water will flow
What are the differences between molecule of an elements and molecules of a compound?
a compound is a pure substance made up of two or more elements chemically combined a molecule is defined as the smallest particle of an element which can exist separately elements are pure substances which can not be split into simple substances by chemical means the atom is defined as the smallest particle of an element which can take part in a chemical change so I think the difference between the molecule of a compound is bigger than the molecule of a compound
Potassium impart purple colour but beryllium do not impart any colour to the flame.Why?
Answer:
The electrons in beryllium and magnesium are too strongly bound to get excited by flame. Hence, these elements do not impart any color.3. A typical peanut butter and jelly sandwich contains 360 kcal, of which 160
kcal comes from fat. Given 1 kcal = 4.2 kJ, how many J of fat would there be
in one PB&J sandwich?
Explanation:
here's the answer to your question
A molecular orbital is a region of space in a covalent species where electrons are likely to be found. The combination of two atomic orbitals always forms two molecular orbitals; the bonding molecular orbital, which is _____ in energy, and the antibonding molecular orbital, which is _____ in energy, than the original atomic orbitals.
Answer:
bonding molecular orbital is lower in energy
antibonding molecular orbital is higher in energy
Explanation:
Electrons in bonding molecular orbitals help to hold the positively charged nuclei together, and they are always lower in energy than the original atomic orbitals.
Electrons in antibonding molecular orbitals are primarily located outside the internuclear region, leading to increased repulsions between the positively charged nuclei. They are always higher in energy than the parent atomic orbitals.
If 56 grams of carbon monoxide burns in oxygen to produce 88 grams of carbon dioxide, the mass of oxygen involved in the reaction is
grams.
The answer is 32 grams!
hope I helped
balance the equation:2Na+3H2O-2NaOH+H2
Answer:
2Na + 2H2O → 2NaOH + H2
Explanation:
A balanced equation is an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for both the reactants and the products.
22.4l of ammonia is reaxts with 1.406 mole of oxygen to produce NO and h2o .1.what volume of no is produced at ntp
Answer:
The volume of NO is 22.4L at STP
Explanation:
Based on the reaction:
2NH3 + 5/2O2 → 2NO + 3H2O
2 moles of NH3 react with 5/2 moles of O2 to produce 2 moles of NO.
To solve this question, we need to find the moles of each reactant in order to find the limiting reactant as follows:
Moles NH3 -Molar mass: -17.01g/mol-
Using PV = nRT
PV/RT = n
Where P is pressure = 1atm at STP
V is volume = 22.4L
R is gas constant = 0.082atmL/molK
T is absolute temperature = 273.15K
1atm*22.4L/0.082atmL/molK*273.15K = n
n = 1.00 moles of NH3
For a complete reaction of 1.00 moles of NH3 are needed:
1.00 moles NH3 * (5/2moles O2 / 2moles NH3) = 1.25 moles of O2
As there are 1.406 moles of O2, the limiting reactant is NH3
The moles of NO produced are the same than moles of NH3 because 2 moles of NH3 produce 2 moles of NO. The moles of NO are 1.00 moles
And as 1.00moles of gas are 22.4L at STP:
The volume of NO is 22.4L at STPHow many moles are in 68 liters of H2S gas at STP? :}
Answe:
Explanation:
số mol của H2S là : 68/22.4=3.03 nha
What unusual physical property does liquid sulfur exhibit from about 113∘C to 230∘C? Select the correct answer below: A. Its vapor pressure decreases with increasing temperature. B. Its vapor pressure increases with increasing temperature. C. Its viscosity decreases with increasing temperature. D. Its viscosity increases with increasing temperature.
Answer:
C. Its viscosity decreases with increasing temperature
Explanation:
The liquid Sulphur is a liquid that turs yellowish green. At a temperature of 120 it tends to melt and has a lower viscosity.A toaster has a resistance of 28 Ω and is plugged into a 110 V circuit. Using the GRASS method, what current is measured?
Answer:
The current of the toaster is 3.93A
Explanation:
Using the GRASS method:
G: Given: The information that is given is that we have 28Ω of Resistance and 110V of voltage.
R: Required: We need to find the current measured.
A: Action: We can use Ohm's law that relates resistance, voltage and current in the equation:
V = R*I
Or:
I = V/R
Where I is current in A, V is voltage = 110V and R is resistance = 28Ω
S: Solve:
I = 110V / 28Ω
I = 3.93A
S: Statement:
The current of the toaster is 3.93AThe seeds of a dandelion are wispy and very light. A single dandelion produces many seeds. How does the structure of the seeds relate to the dandelion's method of spreading seeds?
A Dandelion seeds are spread mainly by the wind. Because they are light, the wind can carry them. The dandelion produces many seeds because not all seeds will land in a good location to sprout.
B. Dandelion seeds are spread primarily by becoming attached to animals' fur. Because they are light, the animals can cany many without noticing. The dandelion produces many seeds because not all seeds will land in a good location to sprout
C. Dandelion seeds are spread mainly by animals that eat them Because they are light the animals will eat many seeds. The dandelion produces many seeds in order to outcompete other plants for resources
D. Dandelion seeds are spread primarily by moving water. Because they are light, they will float on the water. The dandelion produces many seeds in order to outcompete other plants for resources. SIMIT
Answer:
the answer will be number...D
Answer:
The answer is A
Explanation:
Because dandelions are wispy and very light, the slightest gasp of wind helps carry the dandelions to new locations and help reproduce the seed into a new dandelion.
Which of the following would tell you that a weak base is present?
A. An indicator added to the solution turns green-blue.
B. If there is a high reaction rate.
C. If the pH of the solution is close to 14.
D. If the solution is a good conductor of electricity.
Answer:
A. An indicator added to the solution turns green-blue.
Explanation:
A pH scale measures the concentration of hydrogen ions in acidic and alkaline solutions.
In chemistry, pH literally means the power of hydrogen ions and it is a measure of the molar concentration of hydrogen ions in a particular solution; thus, specifying the acidity, neutrality or basicity of any chemical solution.
Mathematically, the pH of a solution is given by the formula;
[tex] pH = -log_{10}(H^{+}) [/tex]
On a pH scale, a solution with a pH of 7 is neutral, a solution with a pH below 7 is acidic and it's basic (alkaline) when it's pH is above 7.
A pH indicator can be defined as a compound (substance) that indicates the concentration of hydrogen ions present in a solution by changing its color over a narrow range of pH values.
A pH range of 1 to 3 (1 - 3) represents a strong acid with a red color.
When an indicator added to a solution turns green-blue, it simply means that a weak base is present.
Which part of a cell directs the cell's activities and holds its DNA?
A. Mitochondrion
B. Ribosome
C. Nucleus
D. Cell membrane
Answer:
Nucleus is the answer
A micrograph of animal cells, showing the nucleus (stained dark red) of each cell. Known as the cell's “command center,” the nucleus is a large organelle that stores the cell's DNA (deoxyribonucleic
Answer:
nucleus is the part of a cell directs the cells Activities and holds it's DNA
what is electrolysis
Answer:
Electrolysis is commercially important as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell
(Q014) Silicates a. are classified on the basis of what kind of metals they contain. b. form through the evaporation of water. c. are a large category of minerals that includes the common minerals calcite and dolomite. d. have the silicon-oxygen tetrahedron as their structural unit.
Answer: d. have the silicon-oxygen tetrahedron as their structural unit.
Explanation:
Silicates are anions that have both Oxygen and Silicon as the basis of their structure. These two form a tetrahedron type structure that enable them to be useful for a whole lot of things.
Silicates are very abundant on Earth as they comprise around 95% of the Earth's crust as well as the upper mantle which explains why they are mostly found in igneous rocks.
PLZ HELP ME Which of the following accurately descnbes the function of the nervous system? O
A To help parts of the body communicate
B. To prevent and fight disease C:
To allow the body to move O
D. To provide support for the body SUNT
Answer:
A
Explanation:
the nervous system helps parts of the body communicate.through nerves.
I hope this helps
When under a pressure of 9.5 atm, a piston has a volume of 1.7 liters. It the piston is compressed to a
volume of 1.1 liters, what will the new pressure be?
c. 8.90 atm
a. 5.08 atm
b. 6.15 atm
d. 14.7 atm
Answer:
D
Explanation:
according to boyle's law the temperature and pressure of a gas are inversely proportional given by the equation
p1v1=p2v2
In this case p1 is 9.5,v1 is 1.7,v2 is 1.1 and we have to find p2
9.5×1.7=p2×1.1
16.15/11=1.1p2/1.2
p2=14.7
I hope this helps
Answer:
[tex]\boxed {\boxed {\sf D.\ 14.7 \ atm}}[/tex]
Explanation:
We are asked to find the pressure on a gas given a change in volume. We will use Boyle's Law which states the volume of a gas is inversely proportional to the pressure. The formula for this law is:
[tex]P_1V_1=P_2V_2[/tex]
The gas originally has a pressure of 9.5 atmospheres and a volume of 1.7 liters.
[tex]9.5 \ atm * 1.7 \ L = P_2V_2[/tex]
The gas is compressed to a volume of 1.1 liters, but the pressure is unknown.
[tex]9.5 \ atm * 1.7 \ L = P_2* 1.1 \ L[/tex]
We want to find the new pressure, so we must isolate the variable P₂. It is being multiplied by 1.1 liters. The inverse operation of multiplication is division. Divide both sides of the equation by 1.1 L.
[tex]\frac {9.5 \ atm * 1.7 \ L}{1.1 \ L} =\frac{ P_2* 1.1 \ L}{1.1 \ L}[/tex]
[tex]\frac {9.5 \ atm * 1.7 \ L}{1.1 \ L} =P_2[/tex]
The units of liters cancel.
[tex]\frac {9.5 \ atm * 1.7 }{1.1 } =P_2[/tex]
[tex]\frac {16.15}{1.1} \ atm =P_2[/tex]
[tex]14.6818181818 \ atm= P_2[/tex]
Round to the tenths place. The 8 in the hundredth place tells us to round the 6 up to a 7.
[tex]14.7 \ atm \approx P_2[/tex]
The new pressure at a volume of 1.1 liters is approximately 14.7 atmospheres.
What is the quantity of carbon-14 in a bone after 17,190 years if the initial mass of C-14 is 0.300 grams and the half-life is 5,730 years?
A.
0.038 g
B.
0.093 g
C.
0.281 g
D.
0.412 g
A. 0.038 g.
Explanation:
The decay of carbon-14 is a first order reaction.
The rate constant of the reaction (k) in a first order reaction = ln (2)/half-life = 0.693/(5730 year) = 1.21 x 10⁻⁴ year⁻¹.
The integration law of a first order reaction is:
kt = ln [Ao]/[A]
k is the rate constant = 1.21 x 10⁻⁴ year⁻¹.
t is the time = 17,190 years.
[Ao] is the initial concentration of carbon-14 = 0.300 g.
[A] is the remaining concentration of carbon-14 = ??? g.
∵ kt = ln [Ao]/[A]
∴ (1.21 x 10⁻⁴ year⁻¹)(17,190 years) = ln (0.300 g)/[A]
2.08 = ln (0.300 g)/[A]
Taking exponential for both sides:
8.0 = (0.300 g)/[A]
∴ [A] = 0.0375 g ≅ 0.038 g
Which of the following structures in the human eye most likely functions in a way to help humans see clearly in different levels of light? A. The iris, or the colored portion of the eye
B. The white area
C. The eyelid
D. The pupil, or the dark portion at the center of the eye
D. the pupil or the dark portion at the center of the eye
What does it mean to view something from a frame reference
Answer:
In physics, a frame of reference, or reference frame, is a perspective that one uses to determine if an object is moving.
For example, when you see a ball roll down a street, you can tell the ball is moving because the frame of reference is the streets, whatever may be on the side of the roads, or the Earth
A gas occupies 210 mL at -73°C to have the same gas occupy 360 mL:
should the temperature be increased or decreased?
what is the new temperature? __ K
Answer:
a. The temperature should be increased.
b. 342.86K
Explanation:
Using Charles law equation as follows:
V1/T1 = V2/T2
Where;
V1 = initial volume (mL)
V2 = final volume (mL)
T1 = initial temperature (K)
T2 = final temperature (K)
According to this question, the following information were given:
V1 = 210mL
V2 = 360mL
T1 = -73°C (-73 + 273 = 200K)
T2 = ?
Using V1/T1 = V2/T2
210/200 = 360/T2
Cross multiply
200 × 360 = 210 × T2
72000 = 210T2
T2 = 72000/210
T2 (new temperature) = 342.86K
calculate the mass of magnesium needed to make 25g of magnesium oxide
Explanation:
here's the answer to your question about
If 16.4 grams of calcium nitrate is heated as shown in the reaction:
2Ca(NO3)2 -> 2CaO + 4NO2 + O2.
Calculate the volume of nitrogen dioxide produced at STP.
Answer:
7.2
Explanation:
you first have to find the number of moles of nitrogen dioxide by using the number of moles for calcium nitrate and the mole to mole ratios
number of moles of calcium nitrate=mass/mm
=16.4/102
=0.16g/mol
then you use the mole to mole ratios
2 : 4
0.16: x
2x/2=0.64/2
x=0.32g/moles of nitrogen dioxide
then you use the formula for the volume
v=22.4n
=22.4×0.32
=7.2
I hope this helps
please answer this questions soon
i will mark him or her brillient
Answer:
1)Or
d.Sublimation
2)
b.iodine is the solute and alcohol is solvent
3)
a.compostion of solute
Answer:
1) a) centrifugation
OR
b) sublimation
2) a) iodine is the solute and alcohol is solvent
3) a) concentration of soLute
Is lithium (Li) more or less reactive than beryllium (Be)? Why?
Answer:
Below!
Explanation:
Lithium (Li) is more reactive than Beryllium (Be). This is because Lithium lacks the valence electron that Beryllium has. Elements with a lower amount of valence electrons are less stable than those with full valence shells, causing it to react more easily. Because Lithium only contains 1 valence electron, it is easily transferred/given up to create bonds and form compounds.
Hope this helps ya! Best of luck <3
Compared to beryllium, lithium (Li) is much more reactive (Be). This is due to Lithium's lack of Beryllium's valence electron.
What is chemical reactivity?Reactivity in chemistry is a gauge of the ease with which a substance reacts chemically. The chemical may react independently or in combination with other atoms and compounds, and in either case, energy will typically be released. The most reactive substances and elements have the potential to spontaneously or explosively ignite.
They typically ignite when exposed to oxygen in the atmosphere and water. Reactivity is temperature-dependent. The available energy for just a chemical reaction increases with temperature, often increasing its likelihood. The noble gases are the least reactive elements. Hydrogen is the least active catalyst in this group and doesn't produce any stable compounds. Compared to beryllium, lithium (Li) is much more reactive (Be). This is due to Lithium's lack of Beryllium's valence electron.
Therefore, compared to beryllium, lithium (Li) is much more reactive (Be). This is due to Lithium's lack of Beryllium's valence electron.
To know more about chemical reactivity, here:
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hii pls help me to balance the equation thanksss
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
[tex]\pmb{\red{\boxed{\sf{Na_{2}O(s)+H_{2}O(l)\dashrightarrow 2NaOH(aq) }}}}[/tex]
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
What is the energy of a photon emitted with a wavelength of 448 nm?
O A. 2.97 x 10-22 J
O B. 4.44 x 10-19 J
O C. 8.91 x
10-23 J
O D. 1.48 x 10-27 J
Answer: B is the correct answer
Explanation:
The energy of a photon is 4.44×[tex]10^{-19}[/tex]J for the wavelength of 448 nm.
So, option (B) is correct. This can be calculated by using the energy formula.
The energy of a photon:The energy of a photon is said to be photon energy. It is directly proportional to the photon's electromagnetic frequency and inversely proportional to the wavelength. If the frequency of the photon is high then its energy is also high.
The energy of a photon, E=hc/λ
Given data:Given that,
λ = 448nm
h= 6.63×[tex]10^{-34}[/tex]J/s
Calculating the energy:E = 6.63×[tex]10^{-34}[/tex]×3×[tex]10^8[/tex]/448×[tex]10^-^9[/tex]
E = 4.44×[tex]10^{-19}[/tex] J
Hence option (B) is correct.
Therefore, the energy of a photon emitted with a wavelength of 448nm is 4.44×[tex]10^{-19}[/tex] J.
Learn more about the energy of photons here:
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How does adding oxygen (O) to this reaction change the equilibrium?
2s02(g) + O2(g) = 2s03(8)
Answer:
The equilibrium shifts right to produce more SO3 molecules.
Explanation:
The equilibrium law states that when a system encounters a disturbance like a temperature, concentration, or pressure modifications, it will react to restore a new state of equilibrium.
Adding a reactant such as oxygen (O2) will shift the reaction in the direction of the product, on the basis of the equilibrium law. Therefore, the equilibrium will move toward the product side.
Sodium nitrate is used in fertilizers, explosives, and glass manufacturing. Give the formula for this compound
How many moles are in 1.7 g of sodium nitrate?
Explanation:
The molecular formula for Sodium Nitrate is NaNO3. The SI base unit for amount of substance is the mole. 1 grams Sodium Nitrate is equal to 0.011765443644878 mole.