Answer:
Explanation:
MW of NaOH = 40 g/mol
MW of KCl = 74.55 g/mp;
250 mL = .25 L
100g NaOH / 40 g = 25 mol
100g KCl/ 74.55g = 1.34 mol
Molarity of NaOH: 25/.25 = 100M
Molarity of KCl: 1.34/.25 = 5.36 M
100M is the concentration of NaOH.
5.36 M is the concentration of KCl.
Define the molarity of a solution.Molarity (M) is the amount of a substance in a certain volume of solution. Molarity is defined as the moles of a solute per litres of a solution.
The scientific noun molarity describes the concentration of a substance as measured by the number of moles divided by the volume of the solution in litres.
[tex]Molality = \frac{Moles \;solute}{Volume\; of \;the \;solution \;in \;litres}[/tex]
Molecular weight of NaOH = 40 g/mol
Molecular weight of KCl = 74.55 g/mp;
250 mL = .25 L
100g NaOH ÷ 40 g = 25 mol
100g KCl ÷ 74.55g = 1.34 mol
Molarity of NaOH: 25 ÷ .25 = 100M
Molarity of KCl: 1.34 ÷ .25 = 5.36 M
Learn more about moles here:
brainly.com/question/8455949
#SPJ2
Answering the following questions will help you focus on the outcomes of the experiments. Experiment 1: What happens to the water in the small tube as the water in the test tube absorbs heat? Why do you think a small tube was used to observe the expansion of water? Experiment 2: Compare the circumference of the balloon before and after freezing. What is the percent increase in this measurement? Combined Results Write a summary paragraph discussing this experiment and the results. Use the following questions and topics to help guide the content of your paragraph. Summarize the conclusions that you can draw from this experiment. Use the questions above to guide your ideas. Summarize any difficulties or problems you had in performing the experiment that might have affected the results. Describe how you might change the procedure to avoid these problems. Describe at least two real-world issues or examples that illustrate the findings of this experiment.
Answer:
Use a glass testtube
Insert a 1-hole stopper in which you insert a glass tube (use a bit of glycerine around the bottom end which makes it slip easier into the stopper)
Fill the testtube with colored water
Place rubber stopper
Make sure there are no air bubbles and that the column in the glass tube is low, as indicated
Place testtube assembly into water which you will heat (hot plate)
Observations
You will observe that the water column in the glass tube moves up as the temperature of the water in the testtube increases. With a 20 mL testtube, and a temperature change from 20 degrees C to 80 degrees C, you should get something like 15-20 cm of change in height.
What do YOU observe?
How do YOU explain your observation?
What is happening there?
Explanation
The water in the testtube expands as it is heated. There is only one direction to expand in, the glass tube. This glass tube is narrow so that a small change in volume will result in a considerable change in height; your signal is amplified.
This is the same phenomenon as in thermometers with a glass bulb on the lower end. Thermometers use a variety of liquids including alcohol (expands more than water) and mercury (is dangerous when spilled).
Explanation:
hope this helps
Answer:
Experiment 1:
What happens to the water in the small tube as the water in the test tube absorbs heat?
Answer: As the water in the test tube absorbs heat the water in the small tube continues to rise
Why do you think a small tube was used to observe the expansion of water?
Answer: The small tube was used to observe the expansion of water to show a visible change that could also be measure with a ruler
Experiment 2:
Compare the circumference of the balloon before and after freezing. What is the percent increase in this measurement?
Answer: The circumference of the balloon increased after it was put in the freezer. The measurement increased by about 5%, it started at 39.5cm then increased to 41.5cm
According to the data, an increase in temperature caused the water molecules to expand because it gained energy which caused it to move more rapidly ultimately resulting in an increase of volume of water. In addition, when being froze water expands making it less dense than the water from which it freezes, causing the volume to also increase. The difficulty I faced in this experiment is pinpointing the exact change in the waters expansion. Two real world issues are when icebergs float as a result of water freezing resulting in expansion, another one is the warming of Earth due to the heat-trapping from greenhouse gases. This heat is absorbed by oceans and seas causing the temperature to rise and the water to expand.
Explanation:
A 0.4505 g sample of a pure soluble bromide compound is dissolved in water, and all of the bromide ion is precipitated as AgBr by the addition of an excess of silver nitrate. The mass of the resulting AgBr is found to be 0.7514 g. What is the mass percentage of bromine in the original compound
Answer:
70.98% is the mass percentage of bromine in the original compound
Explanation:
First, we need to convert mass of AgBr to moles with its molar mass (AgBr: 187.77g/mol). Moles of AgBr = Moles of Br. With molar mass of Br-: 79.904g/mol we can find mass of bromide and mass percentage as follows:
0.7514g AgBr * (1mol / 187.77g) = 0.00400 moles AgBr = Moles of Br-
0.00400 moles Br- * (79.904g / mol) = 0.320g Br- in the sample
Mass percentage is:
0.320g Br- / 0.4505g sample * 100
70.98% is the mass percentage of bromine in the original compoundWhat is the wavelength of a photon that has 4.42 x 10^8 of energy?
Answer:
λ = 4.5×10⁻³⁴ m
Explanation:
Given data:
Energy of photon = 4.42×10⁸ J
Wavelength of photon = ?
Solution:
Formula:
E = hc/λ
speed of light = c = 3×10⁸ m/s
planck's constant = h = 6.63×10⁻³⁴ Js
Now we will put the values in formula.
4.42×10⁸ J = 6.63×10⁻³⁴ Js × 3×10⁸ m/s / λ
λ = 6.63×10⁻³⁴ Js × 3×10⁸ m/s / 4.42×10⁸ J
λ = 19.89×10⁻²⁶ Jm / 4.42×10⁸ J
λ = 4.5×10⁻³⁴ m
How many atoms of fluorine are in 5.6x10^22 molecules of MgF2.
Answer:
1.12 x 10²³atoms of F
Explanation:
Number of MgF₂ atoms = 5.6 x 10²² molecules;
The unknown here is the number of Fluorine atoms found in the compound.
In MgF₂,
1 mole of MgF₂ contains 2 moles of F;
From the given number of molecules we can also say that, MgF₂ contains 5.6 x 10²²atoms;
1 mole of MgF₂ contains 2 moles of F;
5.6 x 10²²atoms of MgF₂ will contain 2 x 5.6 x 10²² = 1.12 x 10²³atoms of F
The number of atoms of Flourine found in 5.6x10^/²² molecules of MgF2 is; 1.12 x 10²³atoms of F
Number of MgF₂ atoms as given = 5.6 x 10²² molecules;
We are required to determine the number of Fluorine atoms found in the compound.
In MgF₂,
1 mole of MgF₂ contains 2 moles of F;As given, MgF₂ contains 5.6 x 10²²atoms;
1 mole of MgF₂ contains 2 moles of F;Hence, 5.6 x 10²²atoms of MgF₂ will contain 2 x 5.6 x 10²² = 1.12 x 10²³atoms of Flourine.
Read more on stoichiometry:
https://brainly.com/question/8062886
Purple flowers are dominant over white flowers. The parent generation includes two heterozygous parents. What are the possible phenotypes of these parents’ offspring? 3 purple and 1 white 3 white and 1 purple 1 purple, 2 lilac, and 1 white 1 white, 2 speckled, 1 purple
A. 3 purple and 1 white. :)
answer on EDGE2020. took/taking the exam.
Purple flowers are dominant over white flowers. The parent generation includes two heterozygous parents. The possible phenotypes of these parents’ offspring are 3 purple and 1 white. Therefore, option A is correct.
What do you mean by phenotype ?A person's genotype is their unique DNA sequence. This term is used to refer to the two alleles that a person inherited for a specific gene. A patient's clinical presentation is the detectable expression of this genotype.
We have three phenotypic classes with one locus and additive effects: AA, Aa, and aa.
Height, wing length, and hair color are all phenotypes. Phenotypes also include observable characteristics that can be measured in the lab, such as hormone levels or blood cell counts.
Purple flowers outnumber white flowers. There are two heterozygous parents in the parent generation. These parents' offspring could have three purple phenotypes and one white phenotype.
Thus, option A is correct.
To learn more about the phenotype, follow the link;
https://brainly.com/question/20730322
#SPJ6
An electrochemical cell is composed of pure nickel and pure iron electrodes immersed in solutions of their divalent ions at room temperature (25°C). If the concentrations of Ni2+ and Fe2+ ions are 0.002 M and 0.40 M, respectively, what voltage is generated at 25°C? (The respective standard reduction potentials for Ni and Fe are −0.250 V and −0.440 V.)
Answer:
0.758 V.
Explanation:
Hello!
In this case, case when we include the effect of concentration on an electrochemical cell, we need to consider the Nerst equation at 25 °C:
[tex]E=E\°-\frac{0.0591}{n} log(Q)[/tex]
Whereas n stands for the number of moles of transferred electrons and Q the reaction quotient relating the concentration of the oxidized species over the concentration of the reduced species. In such a way, we can write the undergoing half-reactions in the cell, considering the iron's one is reversed because it has the most positive standard potential so it tends to reduction:
[tex]Fe^{2+}+2e^-\rightarrow Fe^0\ \ \ E\°=0.440V\\\\Ni^0\rightarrow Ni^{2+}+2e^-\ \ \ E\°=-0.250V[/tex]
It means that the concentration of the oxidized species is 0.002 M (that of nickel), that of the reduced species is 0.40 M and there are two moles of transferred electrons; therefore, the generated potential turns out:
[tex]E=(0.440V+0.250V)-\frac{0.0591}{2} log(\frac{0.002M}{0.40M} )\\\\E=0.758V[/tex]
Beat regards!
Acetylene gas (C2H2) is used in welding torches. When it reacts with oxygen, it produces
carbon dioxide (CO2) and steam (H20). The reaction can be described by the equation 2C2H2+
502 —> 4CO2 + 2H20. How much mass of C2H2 is needed to produce 75.0 grams of CO2?
Mass C₂H₂ needed : 22.165 g
Further explanationReaction
2C₂H₂+ 5O₂ ⇒ 4CO₂ + 2H₂O
75.0 grams of CO₂ , mol CO₂ (MW=44 g/mol) :
[tex]\tt \dfrac{75}{44}=1.705[/tex]
mol C₂H₂ :
[tex]\tt \dfrac{2}{4}\times 1.705=0.8525[/tex]
mass C₂H₂ (MW=26 g/mol) :
[tex]\tt 0.8525\times 26=22.165~g[/tex]
Metal X is soft and can be cut with a knife. It reacts vigorously with air and water. Identify metal X-
iron
copper
Sodium
gold
Answer:
The metal is most likely Sodium.
Explanation:
Iron is not soft enough to be cut with a knife and will not react violently with water. When Iron reacts with water it just slowly rusts.
Copper is somewhat malleable, however, does not really react with water and only forms an oxide layer in the air.
Sodium is soft enough to be cut with a knife (I know this because I have worked with it and seen people work with it). It is also an alkali metal which are known to explode when in water.
Gold is malleable but does not really react with anything and is considered inert.
What would change oxygen into another isotope
Answer:
Adding Neutrons
General Formulas and Concepts:
Chemistry - Atomic Structure
Atoms CompositionNucleus - Protons, NeutronsElectronsExplanation:
We know that adding Protons to any atom will change its chemical properties and make it a different element.
We also know that adding Electrons to any atom will simply only change its overall charge.
Isotopes are formed by adding neutrons to the nucleus. It will be the same element but it would have a different mass and amount of neutrons.
Question 23 of 25
Which of these is a disadvantage of using natural gas?
A. It is not considered safe to use in homes.
B. It burns less cleanly than other fossil fuels.
C. Scientists have developed new ways of extracting it.
D. Extraction through fracking can contaminate groundwater.
SUBMIT
Answer:
the answer is D. extraction through fracking can contaminate groundwater
The disadvantage of natural gas has been the contaminating groundwater due to fracking. Thus, option D is correct.
Natural gas has been the stored fossil energy that has been found buried deep inside the earth. The gas has consisted of a varying quantity of compounds with a maximum proportion of methane.
Natural gas has been nonrenewable, causing pollution with the burning. The release of greenhouse gases with the burning of natural gas results in affecting the environment.
Although there has been the presence of various extraction methods, natural gas results in contaminating groundwater due to fracking. Thus, option D is correct.
For more information about natural gas, refer to the link:
https://brainly.com/question/351648
The naturally occurring isotopes of potassium are potassium-39, potassium-40, and potassium-41. Potassium-39 has an abundance of 93.258% and a mass of 38.964 amu. Potassium-40 has an abundance of 0.011710% and a mass of 39.964 amu. Potassium-41 has an abundance of 6.7302% and a mass of 40.962 amu. Calculate the average atomic mass of potassium
Answer:
39.099 amu
Explanation:
saw this on quizlet no cap sorry im 3 weeks late
To show the electron configuration for an atom, when would it be better to use an orbital notation than to use a written configuration with numbers, letters, and superscripts? when the aim is to use less space when the aim is to show electron spins when the aim is to show orbital shapes in subshells when the aim is to show electron distributions in shells
Answer:
D-when the aim is to show electron distributions in shells
Explanation:
Answer:
D on edge 2021
The equation K + NaOH => Na + KOH should it react, true or false?
Answer:
yes it should react yoyoyoyoyo
What occurs during a solar elcipse
Answer:
the moon gets infront of the sun
Answer:
A solar eclipse happens when the moon moves in front of the Sun as seen from a location on Earth. During a solar eclipse, it gets dimer and dimmer outside as more and more of the Sun is covered by the Moon. During a total eclipse, the entire Sun is covered for a few minutes and it becomes very dark outside. The temperature outside also drops.
- Which particles are found in the nucleus of an argon
atom?
Answer:proton,neutrons,and electrons.
Explanation:
How would the number of oxygen atoms in a 16.00 pound sample compare to the number of sulfur atoms in a 32 pound sample?
1. At room temperature, air is usually a (solid, liquid, gas).
In a mixture of hydrogen and helium gases, the mole fraction of helium is 0.750. If the partial pressure of hydrogen in the mixture is 75 torr, what is the total pressure of the mixture?a. 100 torr b. 300 torr c. 19 torr d. 750 tor e. 760 torr
If the partial pressure of hydrogen in the mixture is 75 torr, the total pressure of the mixture is 100 torr.
What is partial pressure?Partial pressure is the notional pressure present in every gas.
Given,
The mole fraction of helium is 0.750.
The partial pressure of hydrogen in the mixture is 75 torr
The mole fraction of hydrogen is
To find the total pressure
By Roult's law
Partial pressures divided by mole fraction
75 / 0.750 = 100 torr
Thus, the correct option is a, 100 torr.
Learn more about pressure, here:
https://brainly.com/question/356585
1.
Examine the molecule SF4 in the Real Molecules screen to check your prediction from
question c. Which interactions are more important in determining where the lone pair
will go?
Answer:
See explanation
Explanation:
In SF4, the lone pair is placed at an equatorial position. One needs to consider the A-B interactions (axial-equatorial) as well as the B-B (equatorial-equatorial) interactions.
The lone pair occupies an equatorial site to minimize repulsion and maximize the space between electron pairs. Remember that equatorial bonds(Xeq-E-Xeq) are at an angle of 120 degrees while axial bonds(Xax-E-Xeq) lie at an angle of 90 degrees.
It should be noted that in the molecule SF4, the lone pair is placed at an equatorial position.
From the complete question, it's important to consider the axial-equatorial interactions as well as the equatorial-equatorial which is the B-B interactions.
Furthermore, the lone pair occupies an equatorial site that is vital in minimizing repulsion as well as maximizing the space that's between the electron pairs.
In conclusion, the lone pair is placed at an equatorial position.
Read related link on:
https://brainly.com/question/15218635
The initial volume of a gas cylinder is 750 ml if the pressure of a gas inside the cylinder changes from 840 mm hg to 360 mm hg
Answer:
V₂ = 1750 mL
Explanation:
Given data:
Initial volume = 750 mL
Initial pressure = 840 mmHg
Final pressure = 360 mmHg
Final volume = ?
Solution:
The given problem will be solved through the Boly's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
840 mmHg × 750 mL = 360 mmHg × V₂
V₂ = 630,000 mmHg.mL/360 mmHg
V₂ = 1750 mL
Name the two ways by which
suspended impurities present
in water can be removed
Answer:
Common water treatment processes such as flocculation, sedimentation, filtration and disinfection are employed to remove general impurities such as floating and suspended matters, colloidal particles, dissolved organic matter and destruction of disease-causing microorganisms (pathogens).
Explanation:
Lexi is balancing equations. She is finding one equation to be very difficult to balance. Which explains how to balance the equation ZnSO4 + Li2CO3 → ZnCO3 + Li2SO4?
Answer:
deez
Explanation:
thx
Answer:
Atoms in the equation are already in balance
Explanation:
It's D
Ava threw a hamster at her sister the other day she used 12N of force to accelerate the hamster at 8m/s2.what was the mass of the poor hamster?SHOW ALL WORK
We are given:
The force applied on the poor hamster (F) = 12 N
Acceleration of the poor Hamster (a) = 8 m/s²
Solving for the mass of the Poor Hamster:
From newton's second equation of motion, we know that:
F = ma
replacing the given values
12 = 8 * m
m = 12/8 kg
m = 3/2 kg
The poor Hamster weighs 3/2 kg
WILL GET BRAINLIEST AND LOTS OF POINTS IF YOU ANSWER CORRECTLY W EVIDENCE (QUESTION IN PIC BELOW)
Answer:
element,compound
Explanation:
im petty sure this is the anwser
Answer: D
Explanation:
When elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it. true or false
Answer:
True
Explanation:
Lack of employment and income opportunities are pushing large contingents of people to frontier areas and new economic activities, such as gold mining, in the Amazonian region. The number of independent gold miners exceeded 200,000 by 1990. The mining process generates very dangerous and poisonous mercury pollution (mercury is used to separate the gold from other materials), and destroys aquatic and forest habitats. The local population whose diet depends on fish are now threatened by mercury poisoning, as are the miners themselves. –United Nations Research Institute for Social Development Read the text, then use the drop-down menus to complete the statements. People have turned to gold mining because of a lack of opportunities. The is dangerous because it generates mercury .
Answer:
1. employment 2. mining process 3. pollution
Explanation:
I took the assignment, it is 100% correct. : )
Answer:
B
Explanation:
increased pollution
Which of the following statements is true?
The buildup of carbon dioxide in the atmosphere causes the greenhouse effect.
An increase in pressure causes an increase in reaction rate.
The formation of gas bubbles is an indication of a chemical change.
all of the above
Answer:
is there an all of them are true option cause it should be that
Explanation:
your answer to your question is all of the above
Which compound is a polar molecule and has a linear geometry
Answer:
Linear molecule is a molecule in which atoms are deployed in a straight line (under 180° angle). Molecules with an linear electron pair geometries have sp hybridization at the central atom. An example of linear electron pair and molecular geometry are carbon dioxide (O=C=O) and beryllium hydride BeH2.
Explanation:
Sodium sulfate solution contains sodium lons, Na+, sulfate ions, (SO4)2-, hydrogen ions, H+, and hydroxide ions, OH-.
When sodium sulfate is electrolyzed, hydrogen is produced at one electrode and oxygen is produced at the other electrode.
Explain how these products are formed from the ions in the electrolysis process, indicating how you would identify the products.
(6 marks)
Water is oxidized and reduced at both electrodes
Further explanationElectrolysis utilizes electrical energy to carry out non-spontaneous redox reactions. The ions in the solution flowed by an electric current will move toward the electrode opposite the charge.
The negative ions from the solution will move towards the positive electrode, and release electrons around the positive electrode (oxidation occurs) and electrons flow to the negative pole
While around the negative electrode electron binding occurs and a reduction reaction occurs
the reaction at the cathode:
1. the reduced active metal is water, other than that the metal will be reduced
2. H⁺ of the acid will be reduced
For reactions in anode:
1. if the electrodes are not inert then the metal is oxidized
2. If inert then:
a. OH⁻ from the base will be oxidized
b. The halogen metal will oxidize
Na⁺ (cathode)⇒metal group 1 and 2 ⇒ H₂O reduced2H₂O(l)+2e⁻⇒ H₂(g)+2OH⁻(aq)
SO₄²⁻ (anode)⇒acid ion(oxyacid)⇒H₂O oxidized2H₂O(l)⇒4H⁺(aq)+O₂(g)+4e⁻
Explain how electron microscopes work and why some scientists might prefer to use electron microscopes instead of light microscopes.
Answer:
Electron microscopes differ from light microscopes in that they produce an image of a specimen by using a beam of electrons rather than a beam of light. Electrons have much a shorter wavelength than visible light, and this allows electron microscopes to produce higher-resolution images than standard light microscopes.
Explanation: