Answer:
Explanation:
Li(s)+1/2 F₂(g)→LiF(s)
In this reaction one mole of product is formed from gaseous state of reactants . So this reaction will represent the reaction for which ΔH∘rxn equals to ΔH∘f .
In other reaction one mole is not produced if we balance the reaction. The reactant must be in gaseous state . ΔH∘f . represents heat of formation . ΔH∘rxn represents heat of reaction .
Why does a water molecule have a bent shape?
Answer:
The oxygen atom has lone pairs of electrons.
Explanation:
Read The Pros and Cons of Plastic to explore some of the useful properties of plastics.
Which properties of plastics allow them to be solutions to many complex problems in the world? Check all that apply.
chemically resistant
durable
non-reactive
high weight
easy to manufacture
Answer:
chemically resistant
durable
non-reactive
easy to manufacture
Explanation:
Plastics are polymer materials which can be moulded or shaped into any desired shape when hot. There are two types of plastics; thermoplastics and thermo sets.
Most plastics are easily manufactured. They are light weight materials , chemically stable, durable and do not undergo chemical reactions upon prolonged exposure to the atmosphere.
The study of chemicals is called chemistry.
The correct answer is options B, C, and E
The plastic is made by the carbon by joining with itself by a covalent bond and this property of carbon is known as catenation.
In today's time plastic is used all over the world and it is because of the following reasons.
Plastic is durable and long lastPlastic is nonreactive and it does not react to anything and remain stable in the free state.Plastic is easy to manufacture because of the high availability of carbon.Hence, the correct answer is B, C, and E.
For more information, refer to the link:-
https://brainly.com/question/25305623
Which of the following statements is true?
A:Transverse waves move particles parallel to the direction of energy.
B:Longitudinal waves move particles at right angles to the direction of energy.
C:Transverse waves usually occur in solids, while longitudinal waves occur in liquids and gases.
D:All of the above.
Answer:B
Explanation:
state and explain grahms law of diffusion
Answer:
Graham's law of effusion was formulated by Scottish physical chemist Thomas Graham in 1848. Graham found experimentally that the rate of effusion of a gas is inversely proportional to the square root of the mass of its particles. This formula can be written as: , where: Rate₁ is the rate of effusion for the first gas.
Explanation:
r1 = rate of effusion for gas 1
r2 = rate of effusion for gas 2
M1 = molar mass of gas 1
M2 = molar mass of gas 2
How do you round 3795 to THREE sig figs?
Answer:
The answer is 380.
Explanation:
Significant figures:
All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.
Leading zeros are not consider as a significant figures. e.g. 0.06 in this number only one significant figure present which is 6.
Zero between the non zero digits is consider significant like 108 consist of three significant figures.
The zeros at the right side e.g 6300 are also significant. There are four significant figures are present.
How to round the value to three significant figures.
First of all we will place the vertical line after 3rd digit.
379/5
Now we will look at the 4th digit. If it is five or more than five then one is added to 3rd digit. If it is less than five the 3rd digit remain same. In given value 4th digit is 5 thus one is added into 9 and the value become 380.
The answer is 380.
The greater the amount of mass an object has, the more force is needed to move it.
Answer: Newtons Second Law states that acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated), the greater the amount of force needed to accelerate the object (bullet in our case). Everyone inherently knows that heavier objects require more force to move the same distance as lighter objects.
Explanation:
Which element has the electron configuration,
1s2 2s2 2p6 3s2 3p3 4s2 3d10 4p6 5s2 4d5 ?
a
manganese
b
technetium
c
rhenium
d
europium
Answer:
B. technetium
Explanation:
The arrangement of electrons in energy shells is called
Answer:
They are called subshells
electron configuration
Consider the reaction and indicate which reactant is the Lewis acid and which is the Lewis base. C H 3 C O Cl and F e C L 3 give F e C L 4 minus and C H 3 C O plus. The structure of C H 3 C O C L is a central carbon double bonded to an oxygen containing two lone pairs. The central carbon is also bonded to a methyl group and a chlorine, which contains three lone pairs. The product is a central carbon with a plus charge, which is double bonded to an oxygen which contains two lone pairs. THe carbocation is also bonded to a methyl group. Identify the true statement(s).
Answer:
[tex]\mathbf{FeCl_3}[/tex] is the lewis acid
[tex]\mathbf{CH_3COCl}[/tex] is the lewis base
Explanation:
The Lewis acid is a compound capable of accepting a doublet of electrons and which has an electronic gap on its valence layer.
The lewis base is a compound capable of donating a doublet of electrons.
A Lewis acid associates with a Lewis base through a covalent bond (sharing of two electrons between two atoms). The reaction between an acid and a Lewis base produces a compound called the Lewis adduct.
We can see the illustration of the diagrammatic expression in the image attached below.
Viktor tests a solution with a strip of blue litmus paper. The paper turns pink. The solution is a _____.
weak acid
weak base
strong acid
strong base
Answer:
The solution is acidic.
Explanation:
An atom has 9 electrons and 9 protons at the start. If it loses 2 electrons, the net charge on the atom will be
If it loses 2 electrons, the net charge on the atom will be 2. You should first see if the question is already answered next time.
Without SALT or SUGAR, does the water conduct electricity?
I NEED HELPPP THIS DUE TODAY!!!! IT IS URGENT!!
Describe electrons.
Location:
Charge:
mass
Answer:
Describe electrons.
Location: electron cloud
Charge: negative
Mass: one-two thousands amu
Explanation:
How does a scientist make two solutions with the same molarity? A By dissolving the maximum amount of each substance in the B. By dissolving the same number of grams of each substance in the OC. By dissolving 1 mole of each substance in enough water to make same volume of water same volume of water sure dissolving is complete By dissolving the same number of nmoles of each substance in the same volume of water OD.
Answer: The answer is “ By dissolving the same number of nmoles of each substance in the same volume of water ”
Explanation:
By dissolving the same number of moles of each substance in the same volume of water. Hence, option D is correct.
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.
Adding water to a solution and the number of moles of the solvent stay the same while the volume increases.
If there is no flow of solute into or out of the volume during the addition of the solvent, the number of moles of solute remains the same.
Hence, option D is correct.
Learn more about moles here:
brainly.com/question/8455949
#SPJ2
Why is digestion an example of both physical and chemical change simultaneously
Answer: Here is why,
Explanation: Burning of wood is a example of both physical and chemical change. ... Another example is digestion of food ,first the food is chewed into small pieces this is a chemical change while in the actual digestion process it is chemically broken with the help of digestive enzymes and saliva
40.00 grams of NaOH is added into distilled water and diluted with water to 1000mL of final volume. What is the final concentration of the NaOH
Answer:
The molar mass of NaOH is 40.00 g/mol.
The number of moles of NaOH is equal to the ratio of its mass to molar mass.
The number of moles of NaOH =
40 g/mol
40 g
=1,000 mol
The molarity of NaOH solution is the ratio of number of moles of NaOH to total volume of solution in L.
M=
1 L
1 mol
=1 M
Explanation ;)
help pls 100 points and brainiest
Answer:
The amount of salt solution.
Explanation:
so first you have to think about it as a y = mx + b function, where m and x are constants. So basically the independent variable is represented by the amount of salt solution because the health of the patient is affected by the amount of salt solution. this is how you would write it out as an equation so you can understand it better.
The Health of the patient = The amount of salt solution + b
Since y depends on the values of m, x, and b, The amount of salt solution would be the independent variable.
Oliver arrives at the beach to meet his friend Farah. As he walks across the sand, the sand feels hot and burns his bare feet. What type of heat transfer is Oliver experiencing?
Answer:
conduction
Explanation:
The type of heat transfer is Oliver experiencing is Conduction.
What are different types of heat transfer?Heat transfer takes place in three modes,
1. Conduction
2. Convection
3. Radiation
1. Conduction :
Heat energy is transferred through the mechanism of conduction when nearby atoms or molecules collide. In solids and liquids, where particles are more closely spaced, conduction happens more easily than in gases, where particles are more widely spaced.
2. Convection :
Heat is transferred through convection, which is the large-scale movement of molecules inside gases and liquids, fluid motion is responsible for the bulk of the heat transfer.
3. Radiation :
The energy that emanates from a source and moves through space at the speed of light is referred to as radiation.
When Oliver arrives at the beach to meet his friend Farah, the sand feels hot and burns his bare feet as the heat is trapped in the sand and the heat is transferred to Oliver's feet by Conduction.
To know more about types of heat transfer
https://brainly.com/question/4854124
#SPJ6
In a chemistry laboratory, a student filled a 10.0 L container with two (2) different gases. The
gases are nitrogen gas taken from 24.0 L container at 2.00 atm and 12.0 L container of
oxygen at 2.00 atm. If the temperature of the gases is 273 K, calculate the partial pressure
of both gases in the resulting mixture and the total pressure.
Answer:
[tex]P_N=1.33atm\\\\P_O=0.67atm[/tex]
[tex]P_T=2.00 atm[/tex]
Explanation:
Hello.
In this case, the first step is to compute the moles of nitrogen and oxygen given their initial P, T and V conditions via the ideal gas equation:
[tex]n_{N}=\frac{P_{N}V_{N}}{RT} =\frac{2.00atm*24.0L}{0.082\frac{atm*L}{mol*K}*273K}\\ \\n_{N}=2.144molN\\\\n_{O}=\frac{P_{O}V_{O}}{RT} =\frac{2.00atm*12.0L}{0.082\frac{atm*L}{mol*K}*273K}\\ \\n_{O}=1.072molO[/tex]
After that, since the total volume now, once the mixture is formed is the addition between the initial volumes (12.0 L + 24.0 L) is 36.0 L, the partial pressure of each gas turns out:
[tex]P_N=\frac{2.144mol*0.082\frac{atm*L}{mol*K}*273K}{36.0L}\\\\P_N=1.33atm\\\\P_O=\frac{1.072mol*0.082\frac{atm*L}{mol*K}*273K}{36.0L}\\\\P_O=0.67atm[/tex]
Thus, the final total pressure is:
[tex]P_T= P_N+P_O=1.33atm+0.67atm\\\\P_T=2.00 atm[/tex]
Best regards.
A student puts a piece of ice into a beaker of cold water. Which two Statements are true ?A. Thermal energy will move from air to the water. B. Thermal energy will move from the water to the ice. C.Thermal energy will move from the ice to the air . D. Thermal energy will move from the water to the air.
Answer:
C.Thermal energy will move from the ice to the air.
Explanation:
The energy that is associate with the random movement of particles is called thermal energy. The water has a specific heat that is the energy that is needed to raise one gram of a substance to one degree Celsius as water can absorb a large amount of energy and produce a small number of changes the option C.Do all variations help organisms survive
Answer:
Yes
Explanation:
Or maybe i dont really know what it mean
You have 100. grams of potassium fluoride (KF). How many moles do you have? (1 mole KF = 58.09 g KF) *
1.00 mole KF
1.50 mole KF
1.72 mole KF
3.57 mole KF
Answer:
I think its 1.72 (:
Explanation:
what does Ca stand for in chem?
Answer:
Calcium
Explanation:
Periodic table
Cu(NO3)2+Zn(s)>Cu(s)+Zn(NO#)2 is an example of which type of reaction. A) decomposition B) single-displacement C) combustion D) double-displacement
An unknown compound containing only C and H was burnt, yielding 10.2 g of CO2 and 6.3 g of H2O. With a molecular weight of about 30, what is the molecular formula?
Answer:
[tex]C_2H_6[/tex]
Explanation:
Hello.
In this case, we can see that the mass of carbon of the unknown compound comes from the yielded mass of carbon dioxide, thus, we compute the moles of carbon as follows:
[tex]m_C=10.2gCO_2*\frac{1molCO_2}{44gCO_2}*\frac{1mol C}{1molCO_2}=0.232 molC[/tex]
Moreover, the mass of hydrogen comes from the yielded water, therefore we can also compute the moles of water:
[tex]m_H=6.3gH_2O*\frac{1molH_2O}{18gH_2O}*\frac{2molH_2}{1molH_2O} =0.7molH[/tex]
Then, to find the subscripts in the empirical formula, we divide by the moles of carbon as the smallest:
[tex]C:\frac{0.232}{0.232}=1\\ \\H:\frac{0.7}{0.232}=3[/tex]
Whose molar mass is:
[tex]M_{CH_3}=12+1*3=15g/mol[/tex]
Thus, the ratio of the molecular formula to the empirical formula is:
[tex]\frac{30}{15}=2[/tex]
Therefore, the molecular formula is twice the empirical formula:
[tex]C_2H_6[/tex]
Which is actually ethane.
Regards.
The abiotic factor is primary source of energy for all organisms.
Answer:
True, abiotic factors are the primary resources.
Answer: The abiotic factor sunlight is the primary source of energy for living organisms.
Explanation: edmentum/plato
(a) At what substrate concentration would an enzyme with a kcat of 30.0 s−1 and a Km of 0.0050 M operate at one-quarter of its maximum rate? (b) Determine the fraction of Vmax that would be obtained at the following substrate concentrations [S]: ½Km, 2Km, and 10Km. (c) An enzyme that catalyzes the reaction X ⇌ Y is isolated from two bacterial species. The enzymes have the same Vmax but different Km values for the substrate X. Enzyme A has a Km of 2.0 μM, and enzyme B has a Km of 0.5 μM. The plot below shows the kinetics of reactions carried out with the same concentration of each enzyme and with [X] = 1 μM. Which curve corresponds to which enzyme?
The missing graph is in the attachment.
Answer: (a) [S] = 0.0016M
(b) Vmax = 3V; Vmax = [tex]\frac{3V}{2}[/tex]; Vmax = [tex]\frac{11V}{10}[/tex]
(c) Enzyme A: black graph; Enzyme B = red graph
Explanation: Enzyme is a protein-based molecule that speed up the rate of a reaction. Enzyme Kinetics studies the reaction rates of it.
The relationship between substrate and rate of reaction is determined by the Michaelis-Menten Equation:
[tex]V=\frac{V_{max}[S]}{K_{M}+[S]}[/tex]
in which:
V is initial velocity of reaction
Vmax is maximum rate of reaction when enzyme's active sites are saturated;
[S] is substrate concentration;
Km is measure of affinity between enzyme and its substrate;
(a) To determine concentration:
[tex]0.25V_{max}=\frac{V_{max}[S]}{0.005+[S]}[/tex]
[tex]0.25V_{max}(0.005+[S])=V_{max}[S][/tex]
[tex]0.00125+0.25[S]=[S][/tex]
0.75[S] = 0.00125
[S] = 0.0016M
For a Km of 0.005M, substrate's concentration is 0.0016M.
(b) Still using Michaelis-Menten:
[tex]V=\frac{V_{max}[S]}{K_{M}+[S]}[/tex]
Rearraging for Vmax:
[tex]V_{max}=\frac{V(K_{M}+[S])}{[S]}[/tex]
(b-I) for [S] = 1/2Km
[tex]V_{max}=\frac{V(K_{M}+0.5K_{M})}{0.5K_{M}}[/tex]
[tex]V_{max}=\frac{V(1.5K_{M})}{0.5K_{M}}[/tex]
[tex]V_{max}=[/tex] 3V
(b-II) for [S] = 2Km
[tex]V_{max}=\frac{V(K_{M}+2K_{M})}{2K_{M}}[/tex]
[tex]V_{max}=\frac{V(3K_M)}{2K_M}[/tex]
[tex]V_{max}=\frac{3V}{2}[/tex]
(b-III) for [S] = 10Km
[tex]V_{max}=\frac{V(K_{M}+10K_M)}{10K_M}[/tex]
[tex]V_{max}=\frac{V(11K_{M})}{10K_{M}}[/tex]
[tex]V_{max}=\frac{11V}{10}[/tex]
(c) Being the affinity between enzyme and substrate, the lower Km is the less substrate is needed to reach half of maximum velocity.
Km of enzyme A is 2μM and of enzyme B is 0.5μM.
Enzyme B has lower Km than enzyme A, which means the first will need a lower concnetration of substrate to reach half of Vmax.
Analyzing each plot, notice that the red-coloured graph reaches half at a lower concentration, therefore, red-coloured plot is for enzyme B, while black-coloured plot is for enzyme A
. Give two everyday examples of the thermal energy of a substance being increased.
Answer:
• the warmth from the sun
• the heat from another a heater
• A cup of hot chocolate
•baking in an oven
Two everyday example that we say for the thermal energy of a substance being increased are, faster movement of the substances and boiling if liquids as well light absorption.
What is thermal energy?Thermal energy is a form of energy generated by heating up a substance. It can also be generated by the movement of its particles.
Vibrating molecules increases the thermal energy of a substance. Similarly, when we heat a substance it acquires more thermal energy.
Another way of increasing thermal energy is light absorption by the substance. Thermal energy associated with light increases the temperature of of the system which is absorbed the light.
Hence, the two ways by which thermal energy of a substance is increased are heating or boiling and faster movement.
To learn more about thermal energy, refer the link below:
https://brainly.com/question/3022807
#SPJ2
True or false, the nucleus is the core of an atom
Answer:true
Explanation:
The neutrons and the protons are what stay there
