Explanation:
here is the answer. Feel free to ask for more chem help
can anybody pls help me with chemistry how to balance an equation of class 7 ??? pls
really I don't like chemistry..
I need only the step(s)..
Answer:
[tex] This\:may\: help[/tex]
Answer:
(1) Write down the chemical reaction in the form of word equation,keeping reactants on left hand side and products on right hand side.
(2) Write symbol and formula of all reactants and products in word equation. (3) Balance the equation by multiplying the symbols and formula by smallest possible figures.
Question 2 Classify the following statement as a prediction, observation, theory, or law. Please be sure to classify the statement exactly as it is written! A helium filled balloon floats.
Answer:
Theory
Explanation:
We are given the statement;
"A helium filled balloon floats."
Now, this statement is an attempt to explain to us why balloons float. And the reason is because they are filled with helium. This is no prediction or law or observation because to find out if the balloons contain helium, there must have been experiments to confirm that.
Thus, the statement in the question is a theory.
How does science help us understand events in the natural world, and what is chemistry's role in understanding these interactions?
Answer:
See explanation
Explanation:
Science as a body of knowledge seeks to understand the processes that occur in nature so as to offer plausible explanations to those processes as well as redesign nature for our benefit.
Hence, science is an inquiry into nature with the aim to improve the life of the general population of the world.
Chemistry is the study of matter and the changes that matter undergoes. Chemistry lies at the very foundation of science since changes in matter is the basis for the processes that occur in nature.
Hence, chemistry plays a critical role in understanding nature as well as amending nature to improve the living condition of the world's rapidly growing population.
How many moles of
H
C
l
are in
44.1
mL
of a
1.26
M
H
C
l
solution?
Answer: There are 0.0556 moles present in 44.1 mL of a 1.26 M HCl solution.
Explanation:
Given: Volume = 44.1 mL (1 mL = 0.001 L) = 0.0441 L
Molarity = 1.26 M
Molarity is the number of moles of a substance present in liter of a solution.
Therefore, moles of HCl are calculated as follows.
[tex]Moles = \frac{moles}{Volume (in L)}\\1.26 M = \frac{moles}{0.0441 L}\\moles = 0.0556 mol[/tex]
Thus, we can conclude that there are 0.0556 moles present in 44.1 mL of a 1.26 M HCl solution.
How many protons are in Oxygen-18 and how many neutrons are in Copper-65? Please include steps for solving both!
Answer: There are 8 protons in oxygen-18 and 36 neutrons in copper-65.
Explanation:
An atom contains three sub-atomic particles, that is, protons, neutrons and electrons.
The atomic number is the total number of protons present in an atom. For oxygen-18, the atomic mass is 18.
Atomic mass is the sum of total number of protons and electrons present in an atom. As the atomic number of an oxygen atom is 8 so the number of protons present in oxygen-18 is 8.
The atomic mass of copper is 65 and for a copper atom, the atomic number is 29. Hence, the number of neutrons for copper-65 is as follows.
Atomic mass = no. of protons + no. of neutrons
65 = 29 + no. of neutrons
no. of neutrons = 65 - 29 = 36
Thus, we can conclude that there are 8 protons in oxygen-18 and 36 neutrons in copper-65.
For the following reaction, 11.6 grams of sulfur are allowed to react with 23.8 grams of carbon monoxide .
sulfur(s) + carbon monoxide(g) sulfur dioxide(g) + carbon(s)
What is the maximum amount of sulfur dioxide that can be formed?
What is the formula for the limiting reagent?
What amount of the excess reagent remains after the reaction is complete?
Answer:
S + 2CO = SO2 + 2C
First, look for the amount of substance of sulfur:
n(S) = m / M
n(S) = 14.8 g/32 g / mol = 0.4625 mol
n(CO) = m (CO) / M (CO)
M(CO) = 12 + 16 = 28 g/mol
n(CO) = 19.9 g/28 g/mol = 0.71 mol
S in excess, so for calculating we take CO:
n(SO2) = n(CO)/2 = 0.71 mol/2 = 0.355 mol
m(SO2) = M(SO2)*n(SO2)
M(SO2) = 32 + 16*2 = 64 g/mol
m(SO2) = 64 g/mol * 0.355 mol = 22.74 g
What would you expect to observe when Br2 reacts with 2-butyne?
Answer:
I expect to observe a change in colour from reddish brown to a colourless solution
Explanation:
Bromine (Br2) attacks the electron rich carbon-carbon triple bond in but-2-yne, an alkyne to form an initial product 2, 3 dibromobut-2-ene; which reacts with excess bromine to form a final product 2,2,3,3 -tetrabromobutane.
The reaction occurs in two steps. On approaching but-2-yne, bromine molecule becomes polarised forming an induced dipole containing a bromonium ion.
Br - Br → Br+ - Br-
The bromonium ion (Br+) formed then attacks the carbon - carbon triple bond to form the initial product
2,3- dibromobut-2-ene
CH2-C≡C-CH2 + Br+ →
CH2 - CBr =CBr-CH2
(2,3- dibromobut-2-ene)
Which in the presence of excess bromine gives the final product
2,2,3,3 - tetrabromobutane.
CH2 - CBr =CBr-CH2 + Br2 →
CH3 -CBr2-CBr2 - CH3
2,2,3,3 - tetrabromobutane.
A visible change in colour from the reddish-brown colour of Bromine to a colourless solution is observed during the reaction.
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Please, help me.
Someone can teach me English, because I'm from Brazil and if you know how to speak Spanish, it's better for me.
g The theoretical yield of a certain reaction is 123 g of Al2O3. If the actual yield when the experiment is performed is 0.209 mol Al2O3, what is the percent yield
Answer:
Percent yield = 17.3%
Explanation:
The percent yield is defined as 100 times the ratio between actual yield in grams and theoretical yield in grams (123g).
Percent Yield = Actual Yield / Theoretical yield (123g) * 100
To find actual yield we need to convert the 0.209moles to grams:
Actual yield -Molar mass Al2O3: 101.96g/mol-
0.209mol * (101.96g/mol) = 21.3g
Percent yield = 21.3g / 123g * 100
Percent yield = 17.3%
Many chemistry problems result in equations of the form
1.77 X100.298-z)
When this equation is solved, the two values of the unknown are ________ and ________
Answer:
When this equation is solved, the two values of the unknown are 0.0643 and -0.082
Explanation:
Given
[tex]1.77 * 10^{-2} = \frac{x^2}{0.298 - x}[/tex] --- the actual equation
Required
The values of x
We have:
[tex]1.77 * 10^{-2} = \frac{x^2}{0.298 - x}[/tex]
Cross Multiply
[tex]1.77 * 10^{-2} * (0.298 - x)= x^2[/tex]
Multiply both sides by 100
[tex]1.77 * (0.298 - x)= 100x^2[/tex]
Open bracket
[tex]0.52746 - 1.77x= 100x^2[/tex]
Rewrite as:
[tex]100x^2 + 1.77x - 0.52746 =0[/tex]
Using quadratic formula:
[tex]x = \frac{-b \± \sqrt{b^2 - 4ac}}{2a}[/tex]
Where:
[tex]a = 100; b = 1.77; c = -0.52746[/tex]
So, we have:
[tex]x = \frac{-1.77 \± \sqrt{1.77^2 - 4*100*- 0.52746 }}{2*100}[/tex]
[tex]x = \frac{-1.77 \± \sqrt{214.1169}}{2*100}[/tex]
[tex]x = \frac{-1.77 \± 14.63}{200}[/tex]
Split
[tex]x = \frac{-1.77 + 14.63}{200}\ or\ x = \frac{-1.77 - 14.63}{200}[/tex]
[tex]x = \frac{12.86}{200}\ or\ x = \frac{-16.40}{200}[/tex]
[tex]x = 0.0643\ or\ x = -0.082[/tex]
A chemist determines by measurements that 0.0800 moles of bromine liquid participate in a chemical reaction. Calculate the mass of bromine liquid that participates. Round your answer to 3 significant digits.
Answer:
The mass of bromine liquid that participates in a chemical reaction=12.8 g
Explanation:
We are given that
Total number of moles of bromine liquid participate in chemical reaction=0.0800 moles
We have to find the mass of bromine liquid that participates.
Atomic mass of Br=79.9 g
1 mole of bromine liquid=2 atomic mass of bromine (Br)
1 mole of bromine liquid ([tex]Br_2[/tex]) =[tex]2\times 79.9=159.8 g[/tex]
0.0800 moles of bromine liquid=[tex]159.8\times 0.0800[/tex] g
0.0800 moles of bromine liquid=12.784 g
0.0800 moles of bromine liquid[tex]\approx 12.8[/tex] g
Hence, the mass of bromine liquid that participates in a chemical reaction=12.8 g
g Calculate the number of grams of aluminum that is produced in 1.00 h by the electrolysis of molten AlCl3 if the electrical current is 10.0A.
Answer:
3.36 grams Al°(s)
Explanation:
Given AlCl₃(s), determine the mass (grams) of Al°(s) produced from electrolysis of Aluminum Chloride at 10.0 amps for 1.00 hour.
AlCl₃(s) + 378.3°F (=192.4°C) => Al⁺³(l) + 3Cl⁻(l)
formula wt. Al° = 27g/mol
Faraday Constant (F°) = 96,500 amp·sec
? grams Al°(s) = 10.0amps x (1 mole e⁻/96,500amp-sec) x (1 mole Al°(s)/3 mole e⁻) x (27g Al°(s)/1 mole Al°(s)) x 3,600 sec = 3.36 grams Al°(s)
The 3.36 grams of aluminum are produced in 1 hour by the electrolysis of molten AlCl₃ when 10A current is passed.
What is electrolysis?Electrolysis is a process that uses an electrical current to break chemical compounds. The electric current is passed through the substance to bring the chemical change by gain or loss of electrons.
The electrolysis of the aluminum chloride in the molten state is represented as:
AlCl₃ → Al³⁺ + 3Cl⁻
At cathode: Al³⁺ + 3e⁻ → Al (s)
Given, the current. I = 10 A and t = 1 hr = 3600 s
We know that the current is calculated from the equation: I = q/t
q = I× t
q = (10A) × (3600s)
q = 36 × 10³ C
We know, 96500 C of the charge has electrons = 1 mol
36 × 10³ C of the charge has electrons = 0.373 mol
3 moles of electrons required to produce aluminum = 1 mol
0.373 mol of electrons will produce aluminum = 0.373/3 = 0.124 mol
We know that, the mass of one mole of Al = 27g
The mass of 0.124 mol of Al = 27 × 0.124 = 3.36 g
Therefore, the aluminum produced in 1 hour by the electrolysis of molten AlCl₃ is equal to 3.36 grams.
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1) Write a balanced equation to show the reaction of gaseous ethane with gaseous oxygen to form carbon monoxide gas and water vapor.
Answer:
C₂H₆(g) + 2.5 O₂(g) ⇒ 2 CO(g) + 3 H₂O(g)
Explanation:
Let's consider the unbalanced equation in which gaseous ethane reacts with gaseous oxygen to form carbon monoxide gas and water vapor. This is an incomplete combustion reaction.
C₂H₆(g) + O₂(g) ⇒ CO(g) + H₂O(g)
We will balance it using the trial and error method.
First, we will balance C atoms by multiplying CO by 2 and H atoms by multiplying H₂O by 3.
C₂H₆(g) + O₂(g) ⇒ 2 CO(g) + 3 H₂O(g)
Then, we get the balanced equation by multiplying O₂ by 2.5.
C₂H₆(g) + 2.5 O₂(g) ⇒ 2 CO(g) + 3 H₂O(g)
a compound has a percent compostion of carbon equal to 48.8383%, hydrogen equal to 8.1636%, and oxygen equal to 43.1981%. what is the mepirical formula
Answer:
C₂H₃O
Explanation:
From the question given above, the following data were obtained:
Carbon (C) = 48.8383%
Hydrogen (H) = 8.1636%
Oxygen (O) = 43.1981%
Empirical formula =?
The empirical formula of the compound can be obtained as follow:
C = 48.8383%
H = 8.1636%
O = 43.1981%
Divide by their molar mass
C = 48.8383 / 12 = 4.07
H = 8.1636 / 1 = 8.1636
O = 43.1981 / 16 = 2.7
Divide by the smallest
C = 4.07 / 2.7 = 2
H = 8.1636 / 2.7 = 3
O = 2.7 /2.7 = 1
Thus, the empirical formula of the compound is C₂H₃O
What mass of steam initially at 120oC is needed to warm 200g of water in a glass container from 20.0 oC to 50.0 oC
Complete question:
What mass of steam initially at 120 ⁰C is needed to warm 200g of water in a 100 g glass container from 20.0 oC to 50.0 ⁰C
Answer:
the initial mass of the steam is 10.82 g
Explanation:
Given;
mass of water, m₁ = 200 g
mass of the glass, m₂ = 100 g
temperature of the steam = 120 ⁰C
initial temperature of the water, 20⁰ C
final temperature of the water, = 50⁰ C
let the mass of the steam = m
specific heat capacity of water c = 1 cal/g ⁰ C
specific heat capacity of glass c₂ = 0.2 cal/g ⁰ C
laten heat of vaporization of steam L = 540 cal/g
Apply principle of conservation energy;
Heat given off by the steam = Heat absorbed by water + heat absorbed by glass
[tex]mc\Delta T_1 + mL + mc\Delta T_2 = m_1c\Delta T_3 + m_2c_2\Delta T_3\\\\mc\Delta T_1 + mL + mc\Delta T_2 = [m_1c + m_2c_2]\Delta T_3[/tex]
m(1) (120 - 100) + m(540) + m(1) (100 - 50) = [200(1) + 100(0.2)] (50 - 20)
20m + 540m + 50m = 6600
610 m = 6600
m = 6600 / 610
m = 10.82 g
Therefore, the initial mass of the steam is 10.82 g
In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. Which postulate of kinetic molecular theory best explains how this is possible?
A. Attractive forces between gas particles are negligible because the particles of an ideal gas are moving so quickly.
B. Collisions between gas particles are elastic; there is no net gain or loss of kinetic energy.
C. Gases consist of a large number of small particles, with a lot of space between the particles.
D. Gas particles are in constant, random motion, and higher kinetic energy means faster movement.
Answer:
Collisions between gas particles are elastic; there is no net gain or loss of kinetic energy.
Explanation:
When a gas is paced in a container, the molecules of the gas have little or no intermolecular interaction between them. There is a lot of space between the molecules of the gas.
The gas molecules move at very high speed and collide with each other and with the walls of container.
The collision of these particles with each other is perfectly elastic hence the kinetic energy of the colliding gas particles do not change.
list four energy resources
Answer:
Nuclear
Solar
Wind
Hydro
Geo-Thermal
Explanation:
Solar energy from the sun.Geothermal energy from heat inside the earth.Wind energyBiomass from plants.hope it helps
stay safe healthy and happy....How much would the freezing point of water decrease if 4 mol of sugar were added to 1kg of water?
Answer:
7.44 C is the answer of the question.
Explanation:
Determine the kinds of intermolecular forces that are present in each element or compound. Part A KrKr Check all that apply. Check all that apply. dispersion forces dipole-dipole forces hydrogen bonding
Answer:
The kinds of intermolecular forces that are present in each element Kr-Kr.
Explanation:
Since Kr is an inert gas and in atomic form only it is highly stable.
So, Kr gas does not form molecules.
Between the atoms of inert gas, there exist London dispersion forces.
Hence, the intermolecular forces that are present between Kr-Kr atoms is London dispersion forces.
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Which statement describes an electron?
EEEE
It has a positive charge and is located in the nucleus.
O It has a positive charge and is located in orbitals around the nucleus.
It has a negative charge and is located in the nucleus.
O It has a negative charge and is located in orbitals around the nucleus.
Answer:
It has a negative charge and is located in orbitals around the nucleus
Explanation:
The statement describes an electron is " It has a negative charge and is located in orbitals around the nucleus."
What is electron?The electron would be a subatomic particle with a negatively one elementary charge electric charge.
What is nucleus?Protons, that have a positive charge, as well as neutrons, which have no electrical charge, make up the nucleus. Quarks were subatomic particles that make up protons but also neutrons.
Electrons were present surrounding the atom's nucleus, in contrast to protons as well as neutrons, that are contained within the nucleus at its core. Negative electrons were drawn to the positive nucleus since the electric charges of opposite polarity attract one another.
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I have an unknown volume of gas held at a temperature of 115 K in a container with a pressure of 60atm. If by increasing the temperature to 225 K and decreasing the pressure to 30. atm causes the volume of the gas to be 29 liters, how many liters of gas did I start with?
SHOW YOUR WORK
Explanation:
here is the answer to your question.
In a classroom, students who are biochemistry majors are learning about the overall organization of biological membranes. However, one of the students finds a WRONG explanation about the fluid mosaic model from a website and bring it up in a discussion. Which of the following is a WRONG explanation?
a. An explanation of the two-dimensional solutions of oriented lipids and globular proteins.
b. The lipid bilayer is a solvent for integral membrane proteins.
c. All membrane proteins diffuse laterally and freely in the lipid matrix.
d. None of the answers is correct.
e. The lipid bilayer is a permeability barrier for integral membrane proteins.
Answer:
e. The lipid bilayer is a permeability barrier for integral membrane proteins.
Explanation:
Integral membrane proteins enter the lipid bilayer by translocon channel which gives nascent polypeptide segment a chance to partition itself into lipid bilayer hydrophobic core.
What effect would a decrease in volume have on pressure, assuming that temperature (T) and moles of gas (n) are kept constant
Answer:
Pressure increases
Explanation:
Boyle's law states that; '' the volume of a given mass of ideal gas is inversely proportional to its pressure at constant temperature.
Hence, when the volume of a given mass of ideal gas is decreased, the molecules of the gas come closer together so they collide with each other and the walls of the container more frequently.
This implies that the pressure of the gas increases as volume decreases in accordance with Boyle's law.
A student observes a chemical
reaction where two liquids are mixed together. After the liquids are mixed the beaker feels cold to touch. This reactions is an
example of a
reaction.
Synthesis
Combustion
Exothermic
Endothermic
Answer:
Endothermic
Explanation:
Endothermic reaction is one in which the enthalpy increases. What this implies is that, it is a closed system which absorbs heat from its surroundings and thus after reaction become cooler than prior to the reaction.
In this case, the mixture of the two liquids feel colder to touch. Thus, it is an endothermic reaction from the definition earlier given.
Copper reacts with sulfuric acid to yield copper(II) sulfate, water, and sulfur dioxide.
a. True
b. False
Answer:
B. False
Explanation:
Water does NOT react too copper. Copper does not react with water because the oxygen in water is locked into a compound with one part oxygen and two parts hydrogen. Copper oxide is a compound from the two elements copper and oxygen. Everything else listed does but since water is on this list it is false.
In the titration of 82.0 mL of 0.400 M HCOOH with 0.150 M LiOH, how many mL of LiOH are required to reach the equivalence point
Answer:
218.7 mL
Explanation:
The reaction that takes place is:
HCOOH + LiOH → LiCOOH + H₂OFirst we calculate how many HCOOH moles reacted, using the given volume and concentration:
82.0 mL * 0.400 M = 32.8 mmol HCOOHAs 1 HCOOH mol reacts with 1 LiOH mol, 32.8 mmoles of LiOH are needed to react with 32.8 mmoles of HCOOH.
Finally we calculate how many mL of a 0.150 M solution would contain 32.8 mmoles:
32.8 mmol / 0.150 M = 218.7 mLA 25.0 mL sample of a saturated C a ( O H ) 2 solution is titrated with 0.029 M H C l , and the equivalence point is reached after 37.3 mL of titrant are dispensed. Based on this data, what is the concentration (M) of the hydroxide ion?
Answer:
0.043 M
Explanation:
The reaction that takes place is:
Ca(OH)₂ + 2HCl → CaCl₂ + 2H₂OFirst we calculate how many HCl moles reacted, using the given concentration and volume required to reach the equivalence point:
0.029 M HCl * 37.3 mL = 1.0817 mmol HCl = 1.0817 mmol H⁺As 1 mol of H⁺ reacts with 1 mol of OH⁻, in the 25.0 mL of the Ca(OH)₂ sample there are 1.0817 mmoles of OH⁻.
With that in mind we can calculate the hydroxide ion concentration in the original sample solution, using the calculated number of moles and given volume:
1.0817 mmol OH⁻ / 25.0 mL = 0.043 MThe titration is termed the neutralization reaction with the acid and base. The concentration of hydroxide in the titration is 0.0865 M.
What is a neutralization reaction?The neutralization reaction is given as the reaction in which the acid and base react to form the salt and water, stabilizing the pH of the solution.
The neutralization of acid and base to identify the strength can be given as:
[tex]\rm M_V_1=M_2V_2[/tex]
Substituting the strength and the volume of calcium hydroxide and the HCl with the volume:
[tex]\rm 0.029\;M\;\times\;37.3\;mL=M_2\;\times\;25\;mL\\M_2=\dfrac{ 0.029\;M\;\times\;37.3\;mL}{25\;mL} \\M_2=0.0432\;M[/tex]
The strength of the calcium hydroxide in the reaction is 0.04326 M.
One molar unit of calcium hydroxide results in 2 molar units of hydroxide. The molar unit of hydroxide in 0.04326 M calcium hydroxide is:
[tex]\rm 1\;M\;Ca(OH)_2=2\;M\;OH^-\\\\0.04326\;M\;Ca(OH)_2=0.04326\;\times\;2\;M\;OH^-\\0.04326\;M\;Ca(OH)_2=0.0865\;M\;OH^-[/tex]
The concentration of hydroxide ion in the titration is 0.0865 M.
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Please help me ASAP in my final project I am ready to pay 20$
Answer:
$20
ASAP PROJECT
Using the balanced equation for the combustion of ethane: 2C2H6 + 7O2 → 4CO2 + 6H2O, how many moles of O2 needed to produce 12 moles of H2O?
Answer:
14 moles of oxygen needed to produce 12 moles of H2O.
Explanation:
We are given that balance eqaution
[tex]2C_2H_6+7O_2\rightarrow 4CO_2+6H_2O[/tex]
We have to find number of moles of O2 needed to produce 12 moles of H2O.
From given equation
We can see that
6 moles of H2O produced by Oxygen =7 moles
1 mole of H2O produced by Oxygen=[tex]\frac{7}{6}[/tex]moles
12 moles of H2O produced by Oxygen=[tex]\frac{7}{6}\times 12[/tex]moles
12 moles of H2O produced by Oxygen=[tex]7\times 2[/tex]moles
12 moles of H2O produced by Oxygen=14 moles
Hence, 14 moles of oxygen needed to produce 12 moles of H2O.
The amount of oxygen required for the combustion of ethane to produce 12 moles of water is 14 moles.
How are the moles produced in reaction calculated?The moles of oxygen produced in the reaction can be given from the stoichiometric law of the balanced chemical equation.
The balanced chemical equation for the combustion of ethane is:
[tex]\rm 2\;C_2H_6\;+\;7\;O_2\;\rightarrow\;4\;CO_2\;+\;6\;H_2O[/tex]
The 6 moles of water are produced from 7 moles of oxygen. The moles of oxygen required to produce 12 moles of water are:
[tex]\rm 6\;mol\;H_2O=7\;mol\;Oxygen\\12\;mol\;H_2O=\dfrac{7}{6}\;\times\;12\;mol\;O_2\\ 12\;mol\;H_2O=14\;mol\;O_2[/tex]
The moles of oxygen required to produce 12 moles of water are 14 moles.
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what the movement of the earth around the sun
Answer:
Yan po Ang sagot NASA pic
Explanation:
pa heart po plss
at pa vote
CORRECT ME IF IM WRONG
FOLLOW ME AND I FOLLOW BACK YOU☺️☺️☺️♥️♥️
Answer:
The movement of the earth around the sun in a fixed path or orbit is called Revolution. The axis of the earth which is an imaginary line, makes an angle of 66½° with its orbital plane. ... The earth takes about 24 hours to complete one rotation around its axis.