Which is an example of a solution A) air B) oxygen C) salt D) water
Answer:
the answer is A air
Explanation:
Because thats an example of a solution
Two chemical companies can supply a raw material. The concentration of a particular element in this material is important. The mean concentration for both suppliers is the same, but you suspect that the variability in concentration may differ for the two companies. The standard deviation of concentration in a random sample of n1 = 10 batches produced by company 1 is s1 = 4.7 grams per liter, and for company 2, a random sample of n2 = 16 batches yields s2 = 5.8 grams per liter. Is there sufficient evidence to conclude that the two population variances differ? Use α = 0.05.
Answer:
No, there's no sufficient evidence to make a conclusion that the two population variances differ.
Explanation:
Given that:
For company 1
Sample size [tex]n_1[/tex] = 10
Standard deviation [tex]s_1[/tex] = 4.7
For company 2
Sample size [tex]n_2[/tex] = 16
Standard deviation [tex]s_2[/tex] = 5.8
The null hypothesis and the alternative hypothesis can be computed as:
[tex]\mathbf{H_o: \sigma^2_1 = \sigma^2_2}[/tex]
[tex]\mathbf{H_1: \sigma^2_1 \ne \sigma^2_2}[/tex]
Since the alternative hypothesis is ≠, it is then a two-tailed test
Using the F test formula to test for the equality of the variations, we have:
[tex]F = \dfrac{s_1^2}{s_2^2}[/tex]
[tex]F = \dfrac{4.7^2}{5.8^2}[/tex]
[tex]F = \dfrac{22.09}{33.64}[/tex]
F = 0.6567
Hence, the estimated F-value for comparing the standard deviation = 0.6567
The degree of freedom df = ([tex]n_1[/tex] - 1, [tex]n_2[/tex] - 1)
df = ( 10- 1, 16 - 1)
df = (9, 15)
The level of significance ∝ = 0.05
The critical value for a two-tailed test when ∝ = 0.05 and df = (9, 15)
[tex]F_{\alpha/2,n_1 -1,n_2-2} = F_{0.05/2, 9,15}[/tex]
[tex]= F_{0.025, 9,15}[/tex]
by using the Excel function = FINV (0.025,9,15)
= 3.123
Similarly;
[tex]F_{1-\alpha/2,n_1 -1,n_2-2} = F_{1-0.05/2, 9,15}[/tex]
[tex]= F_{0.975, 9,15}[/tex]
Using the Excel function = FINV(0.975,9,15)
= 0.265
Critical Region: To reject the null hypothesis if f ≥ 3.123 or If f ≤ 0.265.
But since The estimated value for F = 0.6567 which is greater than 0.265, we fail to reject the null hypothesis.
Thus, there's no sufficient evidence to make a conclusion that the two population variances differ.
You dissolve 150.0 grams of a mixture of MgCl₂ and KCl in water, add a solution of excess AgNO₃, and precipitate all of the chloride ion as AgCl. After filtration and drying, you find that you have formed 329.0 grams of AgCl. What is the mass in grams of KCl that was in the original 150.0 grams of mixture?
Answer:
112.6g KCl
Explanation:
With the mass of AgCl that we obtain after the precipitation we can obtain its moles = Moles Cl. As all Cl comes from KCl, moles of Cl = Moles KCl + 2*Moles MgCl₂. We can write:
Moles AgCl = Moles Cl
329.0g * (1mol / 143.32g) =
2.2956 moles Cl = Moles KCl + 2 Moles MgCl₂ (1)
150.0g = MolesKCl * 74.5513g/mol + Moles MgCl₂*95.211g/mol (2)
Replacing (2) in (1):
2.2956 moles Cl = 150/74.5513 - 95.211/74.5513 Moles MgCl₂ + 2 Moles MgCl₂
2.2956 = 2.012 - 1.2771Moles MgCl₂ + 2moles MgCl₂
0.2836 = 0.7229 moles MgCl₂
0.392= moles MgCl₂
Mass MgCl₂:
0.392 * (95.211g/mol) = 37.4g MgCl₂
Mass KCl:
KCl = 150.0g - 37.4g =
112.6g KClNeed help with the question.
Answer:
Explanation:
Abundance means: a very large quantity of something. but in chemistry the ratio of the total mass of an element in the earth's crust to the total mass of the earth's crust; expressed as a percentage or in parts per million.
I don't think the abutencies have an effect because I can't find anything.
Hope this helps :D
Describe the location of a proton within an atom. Compare the mass of a proton in regard to other subatomic
particles.
Need help ASAP please
Explanation:
Protons are the positively charged particles found in an atom.
A proton is found within the nucleus of an atom. Together with the neutron, they make up the nuclear region of an atom.Protons and neutrons constitutes the bulk mass of the atom.
The mass of a proton is 1.67 x 10⁻²⁷kg
The proton have the same mass as neutrons.
Compared to electrons, it is 1840 times the mass of an electron.
The nucleus of an atom is where a proton is found. The majority of an atom's mass is located in its nucleus, which is the central part of the atom and is made up of protons and neutrons.
Positively charged protons are what give an element its atomic number and chemical structure. A cloud of negatively charged electrons that are located in particular energy levels or orbits surround the nucleus. In terms of mass, a proton is much heavier than an electron. The mass of a proton is about 1,836 times that of an electron, or 1.67 x 1027 kg.
However, protons have the same mass as neutrons, another subatomic particle present in the nucleus. Protons and neutrons have the same mass, neutrons are slightly heavier.
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Which statements best describe body cells and sex cells? Check all that apply.
Body cells are diploid.
Sex cells are haploid.
Body cells have half the number of chromosomes as sex cells.
Sex cells do not have pairs of chromosomes.
Sex cells are formed during mitosis.
Most cells in humans are body cells.
1 : Body cells are diplod
2 : Sex cells are halplod
3 : Sex cells are formed during chromosomes
4 : Most cells in humans are body cells
Answer:
A- Body cells are diploid.
B- Sex cells are haploid.
D- Sex cells do not have pairs of chromosomes.
F- Most cells in humans are body cells.
Explanation:
Body cells are diploid while sex cells are haploid.
The body generally have two kinds of cells which are;
Gamete cellsBody cellsGenerally, the body cells are more in number than the gamete or sex cells. These gamete cells are passed on from parents to offspring but body cells are not passed on to offspring.
The following statements are true about gamete cells and body cells;
Body cells are diploid. Sex cells are haploid.Sex cells do not have pairs of chromosomes.Most cells in humans are body cells.Learn more: https://brainly.com/question/2673886
PLEASE HELP WITH THESE THREE (30 POINTS)
1) How is the number of neutrons in the nucleus of an atom calculated?
A. Add the number of elections- and protons+ together
B. Subtract the number of elections- from protons+
C. Subtract the number of protons+ from the atomic mass number
D. Add the atomic mass number to the number of elections-
2) Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr) are in the same group on the periodic table. Why? *
A. They have the same size.
B. They react with each other.
C. They have similar properties.
D. They have the same number of protons
3) Which of the following elements would be a transition metal?
A. Ca
B. Au
C. Rb
D. Fr
La longitud de enlace del Bi—I experimental en el triyoduro de bismuto, BiI3, es 2.81 Å. De acuerdo con este valor y con los datos de la figura 7.7, prediga el radio atómico del Bi
Answer:
1,42 Å
Explanation:
La longitud de enlace de Bi-I se obtiene por
Bi-I = Radio del átomo de Bi + Radio del átomo de yodo
pero radio del átomo de yodo = 1.39Å
Longitud del enlace Bi-I = 2,81 Å
Por lo tanto, el radio del átomo de Bi = 2,81 Å - 1,39 Å
radio del átomo de Bi = 1,42 Å
Seismographs are instruments used to ____________.
Question 9 options:
Record the location of the focus
Record size of the break in the Earth’s crust at the epicenter
Record the motion of the ground during an earthquake.
Record topography of the crust in the earthquake zone
Answer:
they are used to record the motion of the ground
Explanation:
Explain why these are the products based on trends in the periodic table (the number of
valence electrons, electronegativity, etc.) for:
CH4 + O2 ------------> CO2 + H2O
Answer:
As more potassium sulfate dissolves in the water, the mixture becomes
Explanation:
As more potassium sulfate dissolves in the water, the mixture becomes
What is the difference between random decay and theoretical?
Answer:
Spontaneous and random. Decay is called spontaneous because the occur on their own and are unaffected by external factors like temperature, pressure, and many more. Decay is called random because we cannot determine the rate at which it decays but can only determine the probability of the decay.Oct 21, 2015
Explanation:
so deku should have more than one quirk because one for all has the power to pass down the user quirk but we all know that all might was quirkless so deku should have 6 quirks to unlock besides one for all he already has black wip and if he was actually had a quirk as a kid he could get it back with the the help of eri thank you if you made it this far TwT heres a potato
Answer:
i never thought about it that way
Explanation:
your right
what type of reaction is being produced for the formula C3H8
Answer:
The balanced chemical equation for the combustion of propane is: C3H8(g)+5O2(g)→3CO2(g)+4H2O(g).
Explanation:
Answer:
chemical reaction if that is answer
Explanation:
please someone help !!!!
Answer:
mass, space, composition, changes, 5, carbon, carbon, organisms, analytical chemistry, physical chemistry, energy transfer, two
Explanation:
Explain why Mercury has a shorter year then earth HURRY IM IN CLASS!!!!!!!!!!
Answer:
Explanation:
This small planet spins around slowly compared to Earth, so one day lasts a long time. Mercury takes 59 Earth days to make one full rotation. A year on Mercury goes by fast. Because it's the closest planet to the sun, it doesn't take very long to go all the way around.
When an object transfers energy to another object, does it always transfer all of it’s energy?
Answer:
Conservation of energy means that the total change of energy in any system is always equal to the total energy transferred into or out of the system.
Answer:
Conservation of energy means that the total change of energy in any system is always equal to the total energy transferred into or out of the system.
Explanation:
Scientists digging in a cave found an unknown substance. The scientists
found that the substance’s molecules were moving around each other. The scientists
increased the speed of the substance’s molecules and caused a phase change. How
did the scientists do this, and how did this affect the substance?
Answer:
By adding heat energy
It changed to gas
Explanation:
A substance whose molecules are moving around each other is a liquid. They are held in shape by very weak intermolecular forces.
For solids, there is no movement because the molecules are held up in a fixed lattice.
Gases molecules moves randomly and independently of one another.
When a liquid is heated and it gains heat energy, it changes phase. A phase change to gas can be predicted. This is because there is an increase in the speed of the substances.
Is the equation 2NO+02 NO, balanced? Explain your answer
Answer:
no its not balanced because we have 2 N in the reactants while we have 1 in the product same for 0 we have 2 0 in the reactants and 1 in the products
for it to be balanced it should be NO + O2 → NO2
Explanation:
A ring made of pure gold contains 5.29 x 1022 atoms. How many moles are in the ring?
Answer:
0.088 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{5.29 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.087873...[/tex]
We have the final answer as
0.088 molesHope this helps you
When the equation
Cu + AgNO3 → Cu(NO3)2 + Ag
is balanced, the coefficient of copper (II) nitrate is
A. 0.
B. 3.
C. 1
An equation which follow the law of conservation of mass is called the balanced equation. The coefficient of copper (II) nitrate is 1 .The correct option is C.
What is a balanced equation?A chemical equation in which the number of atoms of reactants and products on both sides of the equation are equal is defined as the balanced chemical equation.
The coefficients are the numbers which are used to balance the chemical equation. They are added in front of the formulas. According to law of conservation of matter, mass can neither be formed nor be destroyed.
The balanced equation for the given reaction is:
Cu (s) + 2AgNO₃ (aq) → Cu (NO₃)₂ (aq) + 2Ag (s)
Here the coefficient of Cu (NO₃)₂ is 1. The number of 'Cu', 'Ag', 'N' and 'O' atoms are equal. So the given equation is balanced. The coefficient of AgNO₃ is 2, and 'Ag' is 2.
Thus the correct option is C.
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An inflated balloon is left outside overnight. Initially, it has a volume of 38.7 L when the temperature is 255°C and the pressure is 9.4 atm. At what temperature (in °C) will the balloon have a volume of 65.9 L if the pressure falls to 4.2 atm?
When combined in the correct ratio hydrogen and oxygen atoms can form water as shown below
Answer:molecule of a compound
Explanation:
What is the difference between the groups (vertical columns) and periods (horizontal rows) on the periodic table?
Answer:
The vertical columns on the periodic table are called groups or families because of their similar chemical behavior. All the members of a family of elements have the same number of valence electrons and similar chemical properties. The horizontal rows on the periodic table are called periods
a remote control toy jet fighter has a mass of 5 kg and can travel up to 60 m/s. what is the kinetic energy of the toy jet fighter at this speed?
Answer:
9000J
Explanation:
Given parameters:
Mass of the jet fighter = 5kg
Velocity = 60m/s
Unknown:
Kinetic energy of the jet fighter = ?
Solution:
The kinetic energy of a body is the energy due to motion of the body.
It is mathematically expressed as;
K.E = [tex]\frac{1}{2}[/tex] m v²
m is the mass
v is the velocity
So;
K.E = [tex]\frac{1}{2}[/tex] x 5 x 60² = 9000J
Compounds Lab Report
Instructions: In this virtual lab you will build chemical compounds from known elements. Record your hypothesis and compound results in the lab report below. You will submit your completed report to your instructor.
Note: If you cannot complete this lab as directed, please contact your instructor for assistance.
Name and Title:
Include your name, instructor's name, date, and name of lab.
Objectives(s):
In your own words, what is the purpose of this lab?
Hypothesis:
In this section, please include the if/then statements you developed during your lab activity. These statements reflect your predicted outcomes for the experiment.
Procedure:
The materials and procedures are listed in your virtual lab. You do not need to repeat them here. However, you should note if you experienced any errors or other factors that might affect your outcome. Using your summary questions at the end of your virtual lab activity, please clearly define the dependent and independent variables of the experiment.
Data:
Record the composition of each of your compounds below. Be sure to include the number of atoms for each element. An example has been supplied for you.
Compound Name Chemical Formula Sodium (Na) Atoms Calcium (Ca) Atoms Hydrogen (H) Atoms Oxygen (O) Atoms Carbon (C) Atoms Chlorine (Cl) Atoms
Ex: Sodium
hypochlorite NaClO 1 0 0 1 0 1
Conclusion:
Your conclusion will include a summary of the lab results and an interpretation of the results. Please answer all questions in complete sentences using your own words.
Using two to three sentences, summarize what you investigated and observed in this lab.
Why do you believe knowing how elements and compounds react together is essential in everyday matters?
Some elements are more "reactive" than other elements; why do you think this is?
Choose one of the compounds from the table and explain how you know the numbers of atoms in your formula.
Is it possible for two different compounds to be made from the exact same two elements? Why or why not? With a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?
Name and Title:
Colleen DeBruin, Hillary Mulkavits, 11/18/2020, compounds lab.
Objectives(s):
to build chemical compounds from known elements
Hypothesis:
if I use oxygen hydrogen and carbon then I can make five new compounds in four minutes
Procedure:
The materials and procedures are listed in your virtual lab. You do not need to repeat them here. However, you should note if you experienced any errors or other factors that might affect your outcome. Using your summary questions at the end of your virtual lab activity, please clearly define the dependent and independent variables of the experiment.
Data:
Record the composition of each of your compounds below. Be sure to include the number of atoms for each element. An example has been supplied for you.
Compound Name Chemical Formula Sodium (Na) Atoms Calcium (Ca) Atoms Hydrogen (H) Atoms Oxygen (O) Atoms Carbon (C) Atoms Chlorine (Cl) Atoms
Ex: Sodium
hypochlorite NaClO 1 0 0 1 0 1
Water H20 o 0 1 2 0 0
Glucose C6H12O6 0 0 12 6 6 0
Formic/methanoic acid HCOOH 0 0 2 2 1 0
Butanoic Acid C3H7COOH 0 0 8 2 4 0
Carbon Dioxide C02 0 0 0 2 1 0
Carbon Monoxide CO 0 0 0 1 1 0
Fructose C6H12O6 0 0 12 6 6 0
0 0 0
0 0 0
0 0 0
Conclusion:
Your conclusion will include a summary of the lab results and an interpretation of the results. Please answer all questions in complete sentences using your own words.
I found as many combinations of carbon hydrogen and oxygen as possible
If there is a job that combines elements you would be doing that every day making it an every day matter
elements are like people, they are all different causing them to react differently and be more reactive
H20 has four because there are 2 oxygen and one hydrogen because of the numbers in the name of the compound
Yes because two elements can form two different types of bonds causing different outcomes
If this isn't right I'm sorry but I had it as an assignment so we will get it wrong together lol
Please anyone help me
Answer:
It is c
Explanation:
Answer:
W and Z, because they are in the same group as one another
What needs to happen for a chemical change to happen?
How does atomic emission spectra relate to color?
Answer:
Electrons in the gaseous atoms first become excited, and then fall back to lower energy levels, emitting light of a distinctive color in the process. ... An atomic emission spectrum is the pattern of lines formed when light passes through a prism to separate it into the different frequencies of light it contains.
Explanation:
hope this helps u.
In which 2 states of matter can a substance take the shape of its container?
Select one:
solid and gas
solid and liquid
gas and crystal
liquid and gas
Explain the periodic trend for ionization energy and why this occurs?
Answer:
Ionization energy tends to increase across a period because the nuclear pull is increasing while shielding is not changing because electrons are in the same energy level. Not only that as we move across a period elements are closer to a full octet.
Explanation:
