Answer:
0.33 moles
Explanation:
to find the number of moles,
moles = number of atoms / avogadro's number ie 6.02 x [tex]10^{23}[/tex]
moles = 2.0 x [tex]10^{23}[/tex] / 6.02 x [tex]10^{23}[/tex]
moles = 0.33 mol
Suppose that 3.33 g of acetone at 25.0 °C condenses on the surface of a 44.0-g block of aluminum that is initially at 25 °C. If the heat released during condensation goes only toward heating the metal, what is the final temperature (in °C) of the metal block?
Answer:
68.6 °C
Explanation:
From conservation of energy, the heat lost by acetone, Q = heat gained by aluminum, Q'
Q = Q'
Q = mL where Q = latent heat of vaporization of acetone, m = mass of acetone = 3.33 g and L = specific latent heat of vaporization of acetone = 518 J/g
Q' = m'c(θ₂ - θ₁) where m' = mass of aluminum = 44.0 g, c = specific heat capacity of aluminum = 0.9 J/g°C, θ₁ = initial temperature of aluminum = 25°C and θ₂ = final temperature of aluminum = unknown
So, mL = m'c(θ₂ - θ₁)
θ₂ - θ₁ = mL/m'c
θ₂ = mL/m'c + θ₁
substituting the values of the variables into the equation, we have
θ₂ = 3.33 g × 518 J/g/(44.0 g × 0.9 J/g°C) + 25 °C
θ₂ = 1724.94 J/(39.6 J/°C) + 25 °C
θ₂ = 43.56 °C + 25 °C
θ₂ = 68.56 °C
θ₂ ≅ 68.6 °C
So, the final temperature (in °C) of the metal block is 68.6 °C.
The final temperature of the metal block is 74.97°C
What is the specific heat?The specific heat of a substance is the required quantity of heat needed to raise the temperature of 1 gram of the substance by 1° C.
From the parameters given:
The mass of acetone = 3.33 gThe number of moles of acetone is:
[tex]\mathbf{= 3.33 g \times \dfrac{mol}{58.08 \ mol}}[/tex]
= 0.0573 mol
At standard conditions, the heat of vaporization of acetone is:
[tex]\mathbf{\Delta H = 32.0 \ kJ/mol \times 0.0578 \ mol } \\ \\ \mathbf{\Delta H = 1.8496 \ kJ } \\ \\ \mathbf{ \Delta H = 1.85 \times 10^3 \ J}[/tex]
Given that:
The mass of the metal (m) = 44.0 gThe initial temperature [tex]\mathbf{T_1}[/tex] = 25° CThe final temperature [tex]\mathbf{T_2 = ???}[/tex]The specific heat of the aluminum is = 0.903 J/g° C
The heat energy can be computed as:
q = msΔT
q = 41 g × 0.903 J/g° C × (x - 25°C)
Using the calorimetry principle, heat energy lost by metal = heat energy gained by acetone.
i.e.
[tex]\mathbf{q_{(acetone)} gain = q_{(metal)} lost }[/tex]
[tex]\mathbf{-1.85 \times 10^3 \ J = - 41 g \times 0.903 \ J/g^0 C \times ( x - 25^0 c) }[/tex]
[tex]\mathbf{1.85 \times 10^3 \ J = 41 g \times 0.903 \ J/g^0 C \times ( x - 25^0 c) }[/tex]
[tex]\mathbf{(x - 25 ^0 C) = \dfrac{1.85 \times 10^3 \ J }{ 41 g \times 0.903 \ J/g^0 C}}[/tex]
[tex]\mathbf{(x - 25 ^0 C) = 49.97^0 C}}[/tex]
[tex]\mathbf{x = 49.97^0 C+25 ^0 C}}[/tex]
x = 74.97 °C
Learn more about specific heat here:
https://brainly.com/question/1430612
The magnifying power of a telescope is computed by dividing the focal length of its objective by _______.
Answer:
by focal length of the eyepiece.
Explanation:
hope it helps!!plz mark as brainleist.
Between carbon and silicon, which element has the strongest attraction between its nucleus and its valence electrons? Explain?
Answer:
Between carbon and silicon, silicon element has the strongest attraction between its nucleus and its valence electrons.
because silicon's nucleus is bigger than carbon.silicon loses electrons easily than carbon.
is reacts with acid a chemical or physical property? (WORTH 30 Points.)
Answer:
Metals in general have they chemical property of reacting with an acid. Zinc reacts with hydrochloric acid to produce hydrogen gas. This is a chemical property. Chemical change results in one or more substances of entirely different composition from the original substances.
Metal reacts with acid is a chemical property.
Metals react with acids which causes the production of salt and hydrogen gas is released. This is a chemical property because the reactions of reactant produces new type of products which is totally change from the parent material or reactants. The chemical property is refers to change of one type of matter into another type so we can conclude that reaction of metals with acid is a chemical property.
Learn more: https://brainly.com/question/20677720
What is the function of the vacuole?
to make proteins
for storage
to transport materials
to control all cell functions
Explanation:
In animal cells, vacuoles are small and help sequester waste products. In plant cells, vacuoles help maintain water balance. Therefore the answer should be B. For Storage
Hope this helps!
Please mark brainliest!
What causes the wind and weather on earth plz help
can we seperate naphthalene from sugar by filtration to obtain pure sugar?
Answer:
As Naphthalene undergoes sublimation, we use sublimation process. On condensing naphthalene can be separated.
PLS HELP THIS IS DUE TODAY!!
Answer:
I think it would be Yellow
Chloe wants to lighten the color of her dark hair, which will require the use of both haircolor and hydrogen peroxide. Hydrogen peroxide (H2O2) is an example of a(n):
compound molecule.
elemental molecule.
immiscible liquid.
miscible liquid.
Answer:
H₂O₂
Explanation:
Hydrogen peroxide is a typical example of a compound molecule. A compound is made up of one or more atoms that are combined together in a definite grouping.
The properties of a compound is different from those of the elements that combines to from them.
A molecule is a covalent compound that has discrete or separate units. The formula of such compound represents a certain discrete entity. From this problem, we know that hydrogen peroxide is a covalent compoundHow many grams are in 3.00 x 10^24 molecules of Zn(C2H3O2)2?
Answer:
Mass = 917.4 g
Explanation:
Given data:
Number of molecules = 3.00 ×10²⁴ molecules
Mass in gram = ?
Solution:
1 mole contain 6.022 × 10²³ molecules
3.00 ×10²⁴ molecules × 1 mol / 6.022 × 10²³ molecules
0.5×10¹ mol
5 mol
Mass in gram:
Mass = number of moles × molar mass
Mass = 5 mol × 183.48 g/mol
Mass = 917.4 g
Covalent bonds can be single, double, or triple.
How many electrons are shared in a molecule, like O2 that has a double bond?
4
6
12
2
mass = 325.2 volume = 62.5 cm what's the density ?
Answer:
159571 lb or cubic feet
Explanation:
___co+__ Na2s--> ___ Na+ ___ cos2
Answer: [tex]Co+2Na_2S\rightarrow 4Na+CoS_2[/tex]
Explanation:
According to law of conservation of mass, mass can neither be created nor be destroyed. The atoms on the reactant side must be equal to the number of atoms on the product side so that the mass remains the same on reactant and product side. Thus the reactions are balanced.
Single displacement reaction is one where a more reactive element replaces the lesser reactive one.
The balanced chemical reaction will be:
[tex]Co+2Na_2S\rightarrow 4Na+CoS_2[/tex]
How many moles are there in 2.4 x 10 24 atoms of He?
Group of answer choices
6.0 mol
2.4 x 10^24 mol
2.0 mol
4.0 mol
Answer:
4 mol
Explanation:
Given data:
Number of atoms of He = 2.4 × 10²⁴ atoms
Number of moles of He = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
2.4 × 10²⁴ atoms × 1mol / 6.022 × 10²³ atoms
0.398× 10¹ mol
3.98 mol ≅ 4 mol
how can balancing equations support the law of conservation
Answer:
detail is given below.
Explanation:
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
The given equation is balanced chemical equation of photosynthesis. There are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
If equation is not balanced,
CO₂ + H₂O → C₆H₁₂O₆ + O₂
It can not follow the law of conservation of mass because mass is not equal on both side of equation.
i really need help with this question can you guys help me
A certain atom has 50 protons and 69 neutrons. Which statement(s) below are true about this atom? Choose ALL that apply.
this atom is an atom of thulium (Tm)
m this atom has a mass of 69 amu
this atom is an isotope of tin-120
m this atom has an atomic number of 50
Answer:
D.) This atom has an atomic number of 50
Explanation:
A is wrong because we determine the type of atom by their number of protons, not the number of neutrons. This makes the atom Tin (Sn).
B is wrong because both protons and neutrons contribute to the weight of an atom, not just neutrons
C is wrong because the correct name for this isotope would be tin-119, which is calculated by adding the protons and neutrons
D is correct because isotopes of the same element always share the same atomic number
Explain why the answer is correct and why the others aren’t.
Pleaseeee
Answer:
Buffalo and Watertown.
Explanation:
This is correct as the Interior lowlands are located ib the US. These are correct as the others are in the US but aren't located anywhere near the Interior Lowlands.
What is it that lives if it is fed, and dies if you give it a drink
Answer:
fire
Explanation:
Answer:
ants if you splash a ant with sum water that shít is dead
pleae help me I'm so confused
What is the velocity of a person that runs 40 km in 100 hours?
Answer:
0.4 km/h velocity is also the direction their going, in this case the person, that I'll name billy bob joe, is going in so yeh
Explanation:
give me brainliest?
Please help me
There are many different renewable resources available in Florida. Which of the following can be described as a renewable resource?
Consider the reaction below.
2 Na + O2 → Na2O2
If 10.0 g of sodium metal reacts with excess oxygen gas how many grams of sodium oxide will be produced?
Show your work below. Make sure to show ALL units and each step of the process:
Answer:
I think 5
Explanation:
Can someone answer ASAP if you hurry I will mark brainliest
Answer:
Electrical and magnetic
You exert a gravitational force on the pupil and the pupil exerts an equal gravitational force on you. ... The size of the gravitational force depends on the mass of the objects involved. The greater the mass, the greater the gravitational force.
Explanation:
what is the difference between polar and non-polar
Answer:
Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.
Explanation:
Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.
How many different methods can you list for how we generate electricity in this country. Which of those methods do we use the most, and which of them should we invest more in
Answer:
1. Broadly, there are three different methods for how electricity is generated in the United States. They include; Fossil fuels, Nuclear energy, and Renewable energy sources.
2. Fossil fuels, are used the most, with Natural gas topping the list by 38%.
3. More should be invested into renewable gas. It is a clean source of energy and investing in it would bring about a cleaner and safer environment.
Explanation:
Fossil fuels arise from plants and animals that have been long dead and can can now be converted to sources of energy. Examples include; coal natural gas, crude oil. etc.
Nuclear energy arises from the fission of uranium atoms, nuclear decay, and nuclear fusion. They are safe since green house gases are not emitted. Thermal energy can be generated as the byproduct of these reactions.
Renewable sources of energy are generated from natural sources which are always available. Examples are; sun, wind, biomass, water, and geothermal sources,
What is the role of the nervous system?
Answer:
Explanation:
The major regulation, regulatory, and communicating system in the body is the nervous system. It is the foundation of all mental operation, including thinking, learning, and memory. The nervous system, along with the endocrine system, is responsible for controlling and sustaining homeostasis.
Calculate the percentage composition of Aluminum, Sulfur & Oxygen in the compound of Al(SO4)3
Answer:
Percentage of O = 56.1 %
Percentage of Al =15.8%
Percentage of S = 28.1 %
Explanation:
Given compound Al₂(SO₄)₃
Molar mass of compound:
27×2 + 32×3 + 16×12 = 342 g/mol
Percentage of Al = ( Mass of Al / Total mass ) × 100
Percentage of Al = 54 /342 × 100
Percentage of Al =15.8%
Percentage of S = ( Mass of S / Total mass ) × 100
Percentage of S = 96 /342 × 100
Percentage of S = 28.1 %
Percentage of O = ( Mass of O / Total mass ) × 100
Percentage of O = 192 /342 × 100
Percentage of O = 56.1 %
1. 55 grams of salt are added to 100 L of water to make a saline solution.
What is the g/L concentration of the aqueous solution?
Show your work!
Answer:
0.55g/L
Explanation:
Given parameters;
Mass of salt = 55g
Volume of water = 100L
Unknown:
g/L concentration = ?
Solution:
To solve this problem, we must understand that concentration is the amount of solute per solution
g/L concentration = [tex]\frac{55}{100}[/tex] = 0.55g/L
how does a diaphragm help in viewing the specimen in a microscope
Answer:
Diaphragm controls the amount of light reaching the specimen. It is located above the condenser and below the stage. Most high quality microscopes include an Abbe condenser with an iris diaphragm. Combined, they control both the focus and quantity of light applied to the specimen.
If you were to descend through the ocean in a submersible, what changes in the ocean water could you observe?
Answer:
it would become darker. there would be a higher level of water pressure. and there would be less animals, or different alimals.
