Chemistry High School
Answers
Answer 1
Answer:
ΔG = 80,278.67 J/mol
Explanation:
Given:
∆H = - 103.85KJ/mol
∆S = - 269.74KJ/mol
T= 298 K
The Gibbs energy change (ΔG) is calculated as follows:
ΔG = ΔH - TΔS
ΔG = (-103.85KJ/mol)-298K(- 269.74KJ/mol)
ΔG = (-103.85KJ/mol) - (-80,382.52 J/mol)
ΔG = 80,278.67 J/mol
Related Questions
Aluminum metal reacts with aqueous nickel(II) sulfate to produce aqueous aluminum sulfate and nickel as a precipitate. In this reaction 108 g of aluminum were combined with 464 g of nickel(II) sulfate to produce 274 g of aluminum sulfate.
Answers
The question is incomplete, the complete question is;
In this stoichiometry problem, determine the percentage yield:
Excess aluminum metal reacts with aqueous nickel(II) sulfate to produce aqueous aluminum sulfate and nickel as a precipitate. In this reaction 108 g of aluminum were combined with 464 g of nickel(II) sulfate to produce 274 g of aluminum sulfate.
Answer:
80%
Explanation:
The reaction equation is;
2Al(s) + 3NiSO4(aq) --------> Al2(SO4)3 + 3Ni(s)
Since Al is in excess then NiSO4 is the limiting reactant.
Number of moles in 464 g of NiSO4 = mass/ molar mass
Molar mass of NiSO4 = 155 g/mol
Number of moles = 464g/155g/mol = 2.99 moles
Number of moles of Al2(SO4)3 = mass/molar mass
molar mass = 342 g/mol
Number of moles = 274g/342g/mol = 0.8 moles
From the reaction equation;
3 moles of NiSO4 yields 1 mole of Al2(SO4)3
2.99 moles of NiSO4 yields 2.99 * 1/3 = 1 mole of Al2(SO4)3
% yield = actual yield/ theoretical yield * 100/1
actual yield = 0.8 moles of Al2(SO4)3
Theoretical yield = 1 mole of Al2(SO4)3
% yield = 0.8/1 * 100 = 80%
In this exercise we have to use the knowledge of reaction to calculate the required percentage, in this way we find that:
[tex]80\%[/tex]
The reaction equation is;
[tex]2Al(s) + 3NiSO_4(aq) \rightarrow Al_2(SO_4)_3 + 3Ni(s)[/tex]
Since Al is in excess then NiSO4 is the limiting reactant. Now knowing that the data informed is:
Number of moles in 464 g of NiSO4 Molar mass of NiSO4 = 155 g/molNumber of moles = 2.99 molesNumber of moles of Al2(SO4)3Molar mass = 342 g/molNumber of moles = 0.8 moles
From the reaction equation;
[tex]\% yield = actual\ yield/ theoretical\ yield * 100/1\\\% yield = 0.8/1 * 100 = 80%[/tex]
See more about reaction at brainly.com/question/3664113
What is the molarity of a solution made by dissolving .75mol of NaCl in 3.0L of solution?
Answers
molarity equation is moles/liters so it should be .75/3.0=.25
In which sentence does the verb agree with the subject?
Answers
Answer:
go with that persons
Explanation:
describe Bohr’s model of the atom consisted of a central
surrounded by electrons moving in specific
Answers
Answer:
The answer to this question is given below in the explanation section.
Explanation:
The Bohr model depicts an atom as a small, positively charged nucleus surrounded by electrons.These electrons travel in circular orbit around the nucleus similar in structure to the solar system,except electrostatic forces rather than gravity provide attraction.Electron orbit around the nucleus resembles that of planets around the sun in the solar system.
The Bohr model was an improvement on the earlier cubic model(1902),the plum pudding model(1904) the saturnine model (1904) the rutherford model (1911) since the Bohr model is a quantum physics based modification of the Rutherford may source combine the two:the Rutherford-Bohr model
Although revolutionary at the time,the Bohr model is a relatively primitive model of the hydrogen atom compared to the valence shell atom.As an initial hypothesis it was derived as a first order approximation to describe the hydrogen atom.Due to its simplicity and correct results for selected systems.
In 913 Bohr suggested that electrons could only have certain classical motions:
Electrons in atoms orbit the nucleus.The electrons can only orbit stably,without radiating in certain orbits at a certain discrete set of distances from the nucleus.These orbit are associated with definite energies and are also called energy shells or energy levels.Electrons can only gives or lose energy by jumping from one allowed orbit to another,absorbing or emitting electromagnetic radiation with a frequency (v) determined by the energy difference of the levels according to the plank relation.
What is the density of an object that has a mass of 500g and a volume of
10mL?
Answers
Answer:
50 g/mL
Explanation:
Density=mass/volume
Plug in given values
D=500g/10mL
D=50g/mL
I hope this helps!
3. How many grams are in 9.015 x 1035 atoms of Cobalt?
Answers
Answer:
8.822 × 10¹³ g Co
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
9.015 × 10³⁵ atoms Co
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of Co - 58.93 g/mol
Step 3: Convert
[tex]9.015 \cdot 10^{35} \ atoms \ Co(\frac{1 \ mol \ Co}{6.022 \cdot 10^{23} \ atoms \ Co} )(\frac{58.93 \ g \ Co}{1 \ mol \ Co} )[/tex] = 8.82189 × 10¹³ g Co
Step 4: Check
We are given 4 sig figs. Follow sig fig rules and round.
8.82189 × 10¹³ g Co ≈ 8.822 × 10¹³ g Co
These stop the electricity from flowing (examples: glass, rubber). (Lesson 5.03)
A:electric current
B:insulator
C:resistor
D:conductor
Answers
Answer:
B. insulator
hope it helps
The materials which prevents flow of electric current through it is called insulators. Thus, option B is correct. The materials which allow the current are conductors.
What are insulators?
There are three types of substances based on their conducting nature. The materials which are highly conducting electrically at normal condition are called conductors. For example: metals.
Materials which does not conduct electricity at any condition are called insulators. Insulators prevent the flow of free electrons and thus are resistant to electric shock, example: wood
Some materials which does not conduct at normal temperature but, will conduct at higher temperature and also upon mixed with other materials are called semiconductors. example: silicon. Therefore, option B is correct.
To find more on insulators, refer here:
https://brainly.com/question/24909989
#SPJ5
how are molecules, mixtures, and pure substance related
Answers
Answer:
Pure substances are further broken down into elements and compounds. ... A chemical substance is composed of one type of atom or molecule. A mixture is composed of different types of atoms or molecules that are not chemically bonded.
Explanation:
Which of the following is a challenge to democracy shared by both Brazil and Mexico?
A.
People have no economic freedoms.
B.
People accused of a crime have few protections.
C.
Most people do not have the right to vote.
D.
Crime and corruption are serious problems in government.
I’m givin brainliest out also gimme reason
Answers
D.
D. Is the answer because government leaders won’t give their citizens the freedom and opportunities they deserve especially in a democracy.
I hope this helped!
I would appreciate it if you gave me a Thanks and a brainliest (:
define liquor ammonia
Answers
Answer:
ammonia water especially : the impure solution obtained as a by-product in destructive distillation (as of coal, tar, and bones)
Explanation:
Answer:
liquor ammonia is the ammonia water especially , the impure solution obtained as a by-product in destructive distillation (as of coal, tar, and bones)
Balance these equations!
1)
AIBr; +
K-
KBr +
AI
Answers
Answer:
Instructions on balancing chemical equations:
Enter an equation of a chemical reaction and click 'Balance'. The answer will appear below
Always use the upper case for the first character in the element name and the lower case for the second character. Examples: Fe, Au, Co, Br, C, O, N, F. Compare: Co - cobalt and CO - carbon monoxide
To enter an electron into a chemical equation use {-} or e
To enter an ion specify charge after the compound in curly brackets: {+3} or {3+} or {3}.
Example: Fe{3+} + I{-} = Fe{2+} + I2
Substitute immutable groups in chemical compounds to avoid ambiguity.
For instance equation C6H5C2H5 + O2 = C6H5OH + CO2 + H2O will not be balanced,
but PhC2H5 + O2 = PhOH + CO2 + H2O will
Compound states [like (s) (aq) or (g)] are not required.
If you do not know what products are enter reagents only and click 'Balance'. In many cases a complete equation will be suggested.
Reaction stoichiometry could be computed for a balanced equation. Enter either the number of moles or weight for one of the compounds to compute the rest.
Limiting reagent can be computed for a balanced equation by entering the number of moles or weight for all reage
Explanation:
You are a scientist working on increasing the efficiency of appliances to waste less
electricity. You are running experiments measuring the input, output, and waste energy
from 3 light bulbs. Given the data below, determine which model has the lowest
percentage of energy lost as waste.
Lightbulb 1: 200 joules in, 50 joules wasted, 150 joules out
Lightbulb 2: 100 joules in, 30 joules wasted, 70 joules out
Lightbulb 3: 150 joules in, 100 joules wasted, 50 joules out
Answers
Lightbulb 1 has the lowest percentage of energy lost as waste : 25%
Further explanation
Given
The input, output, and waste energy of Lightbulb
Required
The lowest percentage of energy lost as waste.
Solution
Lightbulb 1 :
[tex]\tt \%energy~lost=\dfrac{50}{200}\times 100\%=25\%[/tex]
Lightbulb 2 :
[tex]\tt \%energy~lost=\dfrac{30}{100}\times 100\%=30\%[/tex]
Lightbulb 3:
[tex]\tt \%energy~lost=\dfrac{100}{150}\times 100\%=66.7\%[/tex]
Answer: lightbulb 1: 200 joules in, 50 joules wasted, 150 joules out
Explanation:
What is the resultant pressure if 1.7 mol of ideal gas at 273 K and 2.79 atm in a closed container of constant volume is heated to 315 K? Answer in units of atm.
Answers
Answer: The resultant pressure is 3.22 atm
Explanation:
Gay-Lussac's Law: This law states that pressure is directly proportional to the temperature of the gas at constant volume and number of moles.
[tex]P\propto T[/tex] (At constant volume and number of moles)
[tex]\frac{P_1}{T_1}=\frac{P_2}{T_2}[/tex]
where,
[tex]P_1[/tex] = initial pressure of gas = 2.79 atm
[tex]P_2[/tex] = final pressure of gas = ?
[tex]T_1[/tex] = initial temperature of gas = 273K
[tex]T_2[/tex] = final temperature of gas = 315 K
[tex]\frac{2.79}{273}=\frac{P_2}{315}[/tex]
[tex]P_2=3.22atm[/tex]
Thus the resultant pressure is 3.22 atm
When iso-propanol burns in oxygen, carbon dioxide and water are produced
Answers
Explanation:
When liquidisopropanol(C3H8O)burns in oxygengas,carbon dioxidegas and liquidwater are produced. When dissolved sodium hydroxide reacts with sulfuric acid, aqueous sodium sulfate andwater are formed.
14. What is the total number of kilojoules of heat needed to change 150. G of
ice to water at 0°C?
Answers
Answer:
[tex]\boxed {\boxed {\sf 50.1 \ kJ}}[/tex]
Explanation:
When water changes from ice (solid) to water (liquid), it is melting or fusion. Therefore, we can use the following formula to find energy:
[tex]q=mH_f[/tex]
where q is the energy, m is the mass, and Hf is the heat of fusion.
1. Define Values
The mass is 150 grams. The heat of fusion for water is 334 Joules per gram.
[tex]m= 150 \ g \\H_f=334 \ J/g[/tex]
2. Calculate Energy
Substitute the values into the formula.
[tex]q=150 \ g * 334 \ J/g[/tex]
Multiply. Note that the grams (g) will cancel each other out and leave Joules as our units.
[tex]q=150 *334 \ J[/tex]
[tex]q=50100 \ J[/tex]
3. Convert Units
We found the answer in joules, but the question asks for kilojoules, so we must convert.
There are 1000 Joules in 1 kilojoule. Therefore, we can divide the joules calculated by 1000.
[tex]50100 \ J *\frac{1 \ kJ}{1000 \ J}[/tex]
[tex]\frac{50100 \ kJ}{1000 \ }[/tex]
[tex]50.1 \ kJ[/tex]
50.1 kilojoules are needed to change 150 grams of ice to water.
PLEASE HELP ME ASAP IM DYING
Answers
Answer:
Empirical formula is NH₃
Explanation:
Given data:
Percentage of hydrogen = 82%
Percentage of nitrogen = 18%
Empirical formula = ?
Solution:
Number of gram atoms of H = 18 / 1.01 = 17.8
Number of gram atoms of N = 82 / 14 = 5.9
Atomic ratio:
H : N
17.8/5.9 : 5.9/5.9
3 : 1
H : N = 3:1
Empirical formula is NH₃
What is the name of: CH3-CH(CH3)-CH2- alky group?
isopropyl
propyl
sec-butyl
butyl
Answers
Answer:
propyl
Explanation:
CH3-CH(CH3)-CH2 is a propyl group, the halogen is bromine thus the common name is propyl bromide
explain how to find the mass of water. show your calculations as well
Answers
Answer:
You can find the mass of water by multiplying the density of water by its volume.
mass = Density x volume
Explanation:
It is very easy to find the mass of water once you know the formula of density. "Density" refers to mass per unit volume.
Density (ρ) = [tex]\frac{mass}{volume}[/tex]
Therefore, mass = ρ x volume
The density of water is 1 kg/L.
For example, if the volume of water is 500 ml, then you can get its mass by multiplying 500 ml by 1 kg/L.
Let's convert 500 ml to Liter first.
500 ml x [tex]\frac{1 L}{1,000 ml}[/tex] = 0.5 L
Now, let's compute.
mass = ρ x volume
mass = 1 kg/L x 0.5L
mass = 0.5 kg
The mass of a 500-ml water is 0.5 kg.
3.Write the chemical equation for the reaction when methane burns in (2) (a) Sufficient supply of oxygen (b) Insufficient supply of oxygen
Answers
Answer:
the answer is god
Explanation:
because god created everything therefore hes the answer to everything
Answer:
(a) CH₄ + 2O₂ ----> CO₂ + 2H₂O
(b) 2CH₄ + 3O₂ ----> 2CO + 4H₂O
Explanation:
The burning of methane in an insufficient supply of air leads to incomplete combustion releasing carbon monoxide which is extremely poisonous and cause death.
When methane burnt in air or oxygen, it produces large amounts of heat, together with carbon dioxide and water vapour
Help please!!
in the lab you react 23 g of potassium iodide with an excess of lead (II) nitrate to form 18 g of lead (II) iodide precipitate. What is the percent yield of your experiment?
A) 28
B) 56
C) 84
D) 98
Answers
Answer: A) 28%
This value is approximate.
=============================================
Work Shown:
From the periodic table, we are working with these elements
K = PotassiumI = IodinePb = Lead
and they form these relevant compounds
Potassium iodide = KILead (ii) iodide = [tex]PbI_2[/tex]
Note: the lead (ii) nitrate chemical formula and it's chemical data (eg: atomic mass) doesn't matter so we won't worry about it.
--------------------
Using the periodic table, specifically the atomic mass of each element mentioned, we can find that:
Molar Mass of KI = 166.00277 grams per molMolar Mass of PbI2 = 461.00894 grams per mol
They are approximate values based on the average atomic mass.
Those values are handy in calculating the theoretical yield
That theoretical yield is roughly...
[tex]\left(23 \text{ g } KI\right)*\left(\frac{\text{1 mol } KI}{\text{166.00277 g } KI}\right)*\left(\frac{\text{1 mol } PbI_2}{\text{1 mol} KI}\right)*\left(\frac{\text{461.00894 g } PbI_2}{\text{1 mol } PbI_2}\right)\approx 63.8736668 \text{ g } PbI_2[/tex]
So 23 grams of potassium iodide, and the excess amount of lead (ii) nitrate (the amount of this isn't important as long as it exceeds the potassium iodide amount) react together to produce a theoretical yield of about 63.8736668 grams of lead (ii) iodide precipitate.
-----------------------
Despite us calculating the theoretical yield to be 63.8736668 grams, we actually only got 18 grams. We call this the "actual yield".
To get the percent yield, we divide the actual yield over the theoretical yield and multiply by 100%
So,
[tex]\text{percent yield} = \frac{\text{actual yield}}{\text{theoretical yield}}*100\%\\\\\text{percent yield} \approx \frac{18 \text{ g of } PbI_2}{63.8736668 \text{ g of } PbI_2}*100\%\\\\\text{percent yield} \approx \frac{18}{63.8736668}*100\%\\\\\text{percent yield} \approx 0.2818*100\%\\\\\text{percent yield} \approx 28.18\%\\\\\text{percent yield} \approx 28\%\\\\[/tex]
In short, we expected to get a theoretical amount of roughly 63.87 grams of lead (ii) iodide, but instead we got roughly 28% percent of that theoretical amount and got 18 grams of it instead.
What actions can you take to reduce your impact on science?
Answers
Answer:
Don't travel by air if you can avoid it because air travel uses up large amounts of fossil fuels and creates greenhouse gases. Dispose of any rubbish responsibly - it can be hazardous to wildlife. Use public transport, cycle or walk instead of using a car. Use facilities and trips run by local people whenever possible.
Answer:
Practicing recycling and green computing
Explain why ammonia is a gas at room temperature
Answers
Answer:
Originally Answered: Why isammoniaingasform atroom temperature? That is becauseammonia'sboiling point is -33.34 Celsius or -28 Fahrenheit. The average householdtemperatureis about 28 to 32 Celsius depending where you live but wherever it is, it is definitely above the boiling point ofammonia.GOOD LESSONS ♡
That is because ammonia's boiling point is -33.34 Celsius or -28 Fahrenheit. The average household temperature is about 28 to 32 Celsius depending where you live but wherever it is, it is definitely above the boiling point of ammonia.
which description shows copper at rtp?
a) stationary and closed together
b) stationary and randomly arranged
c)vibrating and in a regular arrangement
d) vibrating and in a random arrangement
Answers
Answer:
c)vibrating and in a regular arrangement
Explanation:
Copper is a chemical element represented by the symbol Cu and having atomic number 29. Copper is a transition metal which means its subshells are not completely filled and that is why they are vibrating in the room temperature. But copper is a solid at room temperature with regular arrangement of atoms.
Hence, the correct answer is "c)vibrating and in a regular arrangement".
I need help with my homework i don't understand nothing
Answers
Answer:
ok so im gonna go and do some for your latest questions then if thats alright with you
Explanation:
i need points so im trying to help as many people as i can before the end of the day.
but you have to make the questions forst so i can help you understand them
what is amphoteric oxide please also give eg
Answers
Answer:
An amphoteric oxide is an oxide that can act as either an acid or base in a reaction to produce a salt and water. Amphoterism depends on the oxidation states available to a chemical species. Because metals have multiple oxidation states, they form amphoteric oxides and hydroxides.Many metals (such as zinc, tin, lead, aluminium, and beryllium) form amphoteric oxides or hydroxides. Amphoterism depends on the oxidation states of the oxide. Al2O3 is an example of an amphoteric oxide. Amphoteric oxides also include Lead (II) oxide, and zinc (II) oxide, among many others.[2]
Explanation:
hope this will help you
Answer:
Amphoteric oxides react with both acids and alkalis to form salt and water. Examples of amphoteric oxides are zinc oxide and aluminium oxide.
Explanation:
hope it helps....
ALUMINUM (AI)
+ NITRATE (NO3)
Answers
Answer:
Al(No3)3
Explanation:
hope this is correct....
1)how many red blood cells could you line up across the grain of sand?
2) How many red blood cells could you line up across the diameter of a penny (0.02 m)?
Please I need helpppppp
Answers
Answer:
The correct answer is -
1. 1 grain of sand = 244 red blood cells.
2. 1 penny = 2439
Explanation:
A normal red blood cell has a normal disk diameter of 6.2 - 8.2 micron or micrometer is way small than a grain of sand which ranges in diameter from 0.0625 mm (or 1⁄16 mm) to 2 mm. The size of the diameter of a penny is given 0.02 m.
Let take the highest value of them:
RBC = 8.2 micrometer
The grain of sand = 2 mm
Penny = 0.02 m
we know:
1 meter = 10e+6 or 100000 micron
1 millimeter = 1000 micron
then, the grain of sand = 2* 1000 = 2000
so, the 1 grain sand = 2000/8.2
= 244
Similarly,
Penny = 0.02*100000= 20000
= 2439
Thus, the correct answer is =
1. 1 grain of sand = 244 red blood cells.
2. 1 penny = 2439
Which of the following statements
is/are true about the region of the
atom labeled "x" in the attached
picture?
Answers
Explanation:
The region x of the atom shown is called the nucleus of the atom shown. The nucleus of an atom contains protons and neutrons.
Protons are the positively charged particles found in the nucleusNeutrons do not carry any charges. Together protons and neutrons determines the mass of the atom. The mass of an atom is concentrated in the nucleusBoth particles have equal masses
The region y is the atomic orbital where electrons can be found.
Zn + I2 ---> Znl2
Determine the theoretical yield of the product if 2g of Zn is used
Answers
Answer:
Mass = 9.58 g
Explanation:
Given data:
Mass of Zn = 2g
Theoretical yield of ZnI₂ = ?
Solution:
Chemical equation:
Zn + I₂ → ZnI₂
Number of moles of Zn:
Number of moles = mass/molar mass
Number of moles = 2g / 65.38 g/mol
Number of moles = 0.03 mol
Now we will compare the moles of Zn and ZnI₂.
Zn : ZnI₂
1 : 1
0.03 : 0.03
Mass of ZnI₂:
Mass = number of moles × molar mass
Mass = 0.03 mol × 319.22 g/mol
Mass = 9.58 g
HELP ASAP MY LESSON IS BEING TIMED!!!
1) Choose the correct answer.
_____ states when one object applies a force on a second object, the second object applies an equal force in the opposite direction.
Newton’s third law of motion
The law of conservation of momentum
The law of conservation of energy
2) Choose the correct answer.
The law of conservation of momentum states that the total movement of a group of objects stays the same unless acted on by _____ forces.
unbalanced
balanced
opposite
3) Choose the correct answer.
Forces work in pairs; the _____ force is the initial force applied to an object.
momentum
action
reaction
Answers
Answer:
1. Newton's third law of motion
2. Unbalanced
3. Action
It’s action for number 3