Answer:
C- A foot
Particularly a muscular foot.
Answer/Explanation
you"re right they have a foot
Muscular foot for creeping or burrowing. Some also have a head with sense organs.
did u need someone to confirm it or what
Can you give me the answers to questions 28 and 29 please?
28. unbalanced because in reactant side the Aluminium is 1 and oxygen is 2 but in the product side the Aluminium is 2 and oxygen is 3 it is not equal so it is unbalanced equation
29. unbalanced because the oxygen atom are not equal in the reactant and the product side
Follow me pls!!
Imagine an alternate universe where the value of the Planck constant is 6.6207 x 10^-36 J*s.
In that universe, which of the following objects would require quantum mechanics to describe, that is, would show both particle and wave properties? Which objects would act like everyday objects, and be adequately described by classical mechanics?
1. A buckyball with a mass of 1.2 x 10-21 g, 0.7 nm wide, moving at 38. m/s.
classical or quantum?
Answer:
See explanation
Explanation:
According to Louis de Broglie, matter has an associated wavelength. He was the first scientist to establish the idea of wave-particle duality or wave- particle paradox.
The display of wavelike properties by objects in the universe is dependent on the magnitude of the of the mass of the body. Small objects have a large associated wavelength and can be described completely by quantum mechanics.
A buckyball with a mass of 1.2 x 10-21 g, 0.7 nm wide, moving at 38. m/s has a very small mass and significant associated wavelength hence the system can be completely described by quantum mechanics.
A mixture is made by combining 1.29 lb of salt and 5.35 lb of water.
What is the percentage of salt (by mass) in this mixture?
Answer:
19.47%
Explanation:
[tex]\frac{1.29}{1.29+5.35}[/tex]
Please recheck, for this answer may not be correct
True or false: potential energy increases as like charges get closer to one another
What happens to water when it changes to ice
Answer:The atoms cool down and become slower and their bonds become close and they move less.
Explanation:I took science
Need help asap!
1. Given that the electronegativity of sulfur (S) is 2.5 and that of silicon (Si) is 1.8, which of the following best describes the chemical bonding in silicon monosulfide (SiS)?
A. ionic: transfer of electrons from silicon to sulfur
B. nonpolar covalent: equal sharing of electrons between silicon and sulfur
C. polar covalent: electrons shared between silicon and sulfur but attracted more to the sulfur
D. polar covalent: electrons shared between silicon and sulfur but attracted more to the silicon
2. Which of the following is a molecular compound?
A. Mg3N2
B. NH3
C. AlCl3
D. LiBr
3. Potassium (K) reacts with a certain nonmetallic element (Z) to form a compound with the general formula KZ; where element Z is a diatomic gas at room temperature. What is element Z?
A. Oxygen
B. Fluorine
C. Nitrogen
D. Hydrogen
Answer: 1. C. polar covalent: electrons shared between silicon and sulfur but attracted more to the sulfur
2. B) [tex]NH_3[/tex]
3. B) Fluorine
Explanation:
1. A polar covalent bond is defined as the bond which is formed when there is a difference of electronegativities between the atoms.
Electronegativity difference = electronegativity of sulphur- electronegativity of silicon = 2.5 -1.8 = 0.7
Thus as electronegativity difference is less than 1.7 , the cond is polar covalent and as electronegativity of sulphur is more , the electrons will be more towards sulphur.
2. A molecular compound is usually composed of two or more nonmetal elements. Example: [tex]NH_3[/tex]
Ionic compound is formed by the transfer of electrons from metals to non metals. Example: [tex]Mg_3N_2[/tex] , [tex]AlCl_3[/tex] and [tex]LiBr[/tex]
3. For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here K is having an oxidation state of +1 and as the compound formed is KZ, the oxidation state of non metallic element Z should be -1. Thus the element Z is flourine which exists as diatomic gas [tex]F_2[/tex]
How many molecules are in 20,484 grams of H2O?
Answer:
3.4027x10^-22
Explanation:
A 0.500-gram sample of a weak, nonvolatile monoprotic acid, HA, was dissolved in sufficient water to make 50.0 milliliters of solution. The solution was then titrated with a standard NaOH solution. Predict how the calculated molar mass of HA would be affected (too high, too low, or not affected by the following laboratory procedures. Explain each of your answers.
a. After rinsing the buret with distilled water, the buret is filled with the standard NaOH solution; the weak acid HA is titrated to its equivalence point.
b. Extra water is added to the 0.500-gram sample of HA.
(a) An indicator that changes color at pH 5 is used to signal the equivalence point.
(b) An air bubble passes unnoticed through the tip of the buret during the titration.
Answer:
Follows are the solution to the given points:
Explanation:
It is expected to be too low a calculated molecular weight. It is because NaOH is diluted throughout washing with distilled water. It means that its measured intensity would be too high. Mwt implies Mwt now. Oh, Mwt. It's low. If the water becomes inserted throughout the acid HA, the molarity Across would not be impacted as the acidic mole remains unchanged despite water added to the acidic Ha. It's going to be much too big a molecular weight. Its measurement indicates the middle state at PH=5, well before this neutral point, so that if the NaOH reading is less, and the value of the strength of HA would consequently become lower. So m/Mwt=low shows Mwt=high.Its real measurement will be less because of the air pocket in the office. Even so, because of an unknown bubble interpretation, more is removed. Its intensity of acid is, therefore, less measured, and thus Mwt is also too high.Mount Everest is 29,029 feet high. What is
the height of Mount Everest in kilometers?
Answer:
8.849 kilometres
Explanation:
this is the height in kilometers
Analysis of an unknown substance indicates that it is a brittle solid. It acts as an electrical insulator (does not conduct) as a solid but conducts electricity when melted. Which of the following substances would have these characteristics?
a. HCl
b. Al
c. KBr
d. SiF4
e. I2
Answer:
KBr
Explanation:
A metal has a very high melting point. Aluminum is a metal.
Ionic solids do not conduct electricity in the solid state. However, when the solids are melted, they conduct electricity.
KBr is an ionic substance, it can only conduct electricity in molten form because the ions are locked up in the solid.
Can you please help me
Shure what you need help with
Identify the good electrical conductor. Carbon Copper Nitrogen Sulfur
is a planar carbon "backbone" possible for propane? Explain.
Is a planar carbon "backbone" possible for cyclopropane? Explain.
Answer:
Cyclopropane has a planar carbon back bone while propane does not
Explanation:
We have to recognize that in straight chain saturated organic compounds, carbon atoms have a tetrahedral geometry. Each carbon atom is bonded to four other atoms.
However, carbon atoms in cyclic compounds are also sp3 hybridized with each carbon bonded to only four other atoms but the ring system is highly strained.
Cyclopropane is a necessarily planar molecule with a bond angle that is far less than the expected tetrahedral bond angle due to strain in the molecule. Hence, the carbon atoms may have have a "planar backbone".
The following graph shows a decay chain. Which part of the decay chain will take the most time?
Propane is what type of matter?
Element
Compound
Homogeneous mixture
Heterogeneous mixture
The density of toluene (C7H8) is 0.867 g/mL, and the density of thiophene (C4H4S) is 1.065 g/mL. A solution is made by dissolving 8.10 g of thiophene in 250.0 mL of toluene.
(a) Calculate the mole fraction of thiophene in the solution.
(b) Calculate the molality of thiophene in the solution.
(c) Assuming that the volumes of the solute and solvent are additive, what is the molarity of thiophene in the solution?
Considering the solution of mole fraction, molality and molarity, you obtain that:
(a) the mole fraction of thiophene in the solution is 0.039.
(b) the molality of thiophene in the solution 0.4429 [tex]\frac{moles}{kg}[/tex].
(c) the molarity of thiophene in the solution is 0.373[tex]\frac{moles}{L}[/tex].
You know that:
Density toluene (C₇H₈)= 0.867 [tex]\frac{g}{mL}[/tex]Density thiophene (C₄H₄S)= 1.065 [tex]\frac{g}{mL}[/tex] Volume of toluene (C₇H₈)= 250 mL= 0.250 L (being 1000 mL= 1 L)Mass of thiophene (C₄H₄S)= 8.10 grams(a) Mole fractionThe molar fraction is a way of measuring the concentration that expresses the proportion in which a substance is found with respect to the total moles of the solution.
Being the molar mass of each compound equals to:
Toluene (C₇H₈)= 92 [tex]\frac{g}{mol}[/tex]Thiophene (C₄H₄S)= 84 [tex]\frac{g}{mol}[/tex]the number of moles of each compound can be calculated as:
Toluene (C₇H₈)= [tex]250 mLx\frac{0.867 grams}{1 mL} x \frac{1 mole}{92 grams}[/tex]= 2.35 molesThiophene (C₄H₄S)= [tex]8.10 gramsx\frac{1 mole}{84 grams}[/tex]= 0.096 molesThe total moles is obtained from the addition of the moles of the solute (C₄H₄S) and the solvent (C₇H₈):
total moles = moles C₄H₄S + moles C₇H₈ = 0.096 moles + 2.35 moles = 2.45 moles
Then, the mole fraction of thiophene in the solution can be calculated as:
[tex]mole fraction of thiophene=\frac{0.096 moles}{2.45 moles}[/tex]
Solving:
mole fraction of thiophene= 0.039
Finally, the mole fraction of thiophene in the solution is 0.039.
(b) MolalityMolality is the ratio of the number of moles of any dissolved solute to kilograms of solvent.
The Molality of a solution is determined by the expression:
[tex]Molality=\frac{number of moles of solute}{kilograms of solvent}[/tex]
In this case, you know:
number of moles of solute (C₄H₄S)= 0.096 moles Mass of solvent = [tex]250 mLx\frac{0.867 grams}{1 mL}[/tex] = 216.75 g = 0.21675 kg (being 1000 g=1 kg)Replacing:
[tex]Molality C_{4} H_{4}S =\frac{0.096 moles}{0.21675 kg}[/tex]
molality C₄H₄S= 0.4429 [tex]\frac{moles}{kg}[/tex]
Finally, the molality of thiophene in the solution 0.4429 [tex]\frac{moles}{kg}[/tex].
(c) MolarityMolarity is the number of moles of solute that are dissolved in a certain volume and is determined by the following expression:
[tex]Molarity=\frac{number of moles of solute}{volume}[/tex]
Assuming that the volumes of solute and solvent are additive, you can add the volume of C₄H₄S and C₇H₈.
But first, you need yo know the volume of C₄H₄S, which can be calculated from the mass and density:
[tex]Volume C_{4} H_{4}S =8.10 grams\frac{1 mL}{1.065 grams}[/tex]= 7.606 mL= 0.007606 L
Then, the total volume of the solution is calculated as:
total volume of the solution= volume C₇H₈ + volume C₄H₄S
total volume of the solution= 0.250 L + 0.007606 L = 0.257606 L
So, the molarity of thiophene in the solution can be calculated as:
[tex]Molarity C_{4} H_{4} S=\frac{number of moles of C_{4} H_{4} S}{totalvolumeof the solution}[/tex]
Replacing:
[tex]Molarity C_{4} H_{4} S=\frac{0.096 moles}{0.257606 L}[/tex]
Solving:
Molarity C₄H₄S= 0.373 [tex]\frac{moles}{L}[/tex]
Finally, the molarity of thiophene in the solution is 0.373[tex]\frac{moles}{L}[/tex].
In summary, you get:
(a) the mole fraction of thiophene in the solution is 0.039.
(b) the molality of thiophene in the solution 0.4429 [tex]\frac{moles}{kg}[/tex].
(c) the molarity of thiophene in the solution is 0.373[tex]\frac{moles}{L}[/tex].
Learn more about
density: brainly.com/question/952755?referrer=searchResults brainly.com/question/1462554?referrer=searchResults mole fraction: brainly.com/question/14434096?referrer=searchResults brainly.com/question/10095502?referrer=searchResults molality brainly.com/question/20366625?referrer=searchResults brainly.com/question/4580605?referrer=searchResults molarity with this example: brainly.com/question/15406534?referrer=searchResultsA 50.0mL flask filled with a solution of hydrogen peroxide has a total mass of 88.5 g. The mass of the flask is 16.5 g. The density of the hydrogen peroxide solution is
Answer:
1.44 g/mL
Explanation:
total mass is mass of the flask plus mass of the solution
TM = Flask + H2O2
88.5 = 16.5 + x
x = 72.0 gram
density = mass/volume
H2O2 density = 72/50
= 1.44 g/mL
What is the ratio of hydrogen atoms to oxygen atoms in a water molecule?
The specific heat capacity of methane gas is 2.20 J/g-K. How many joules of heat are needed to raise the
temperature of 5.00 g of methane from LaTeX: 36.0^\circ C36.0 ∘ C to LaTeX: 75.0^\circ C75.0 ∘ C?
Heat needed to raise the temperature : Q = 3432 J
Further explanationGiven
c = The specific heat capacity = 2.20 J/g-K
m = mass = 5 g
Δt = Temperature difference = 75-36 =39 °C=312 K
Required
Heat needed
Solution
Heat can be formulated
Q = m.c.Δt
Input the values :
Q = 5 g x 2.2 J/g-K x 312 K
Q = 3432 J
What is the correct name of CUCIO2
Chemistry
Answer:
Copper(II) Chlorite = Cu(ClO2)
Explanation:
how you write the compound is very important as well
Which macromolecules break apart by hydrolysis?
Answer:
Dehydration synthesis reactions build molecules up and generally require energy, while hydrolysis reactions break molecules down and generally release energy. Carbohydrates, proteins, and nucleic acids are built up and broken down via these types of reactions, although the monomers involved are different in each case.
Explanation:
Calculate the temperature change when 2.00 L at 293 K is compressed to 1.00 L.
Answer:
[tex]\Delta T=-146.5K[/tex]
Explanation:
Hello!
In this case, given the Charles' law which allows us to understand the volume-temperature behavior as shown below:
[tex]\frac{T_1}{V_1}=\frac{T_2}{V_2}[/tex]
Thus, given that we need to calculate the final temperature after the compression, we obtain:
[tex]T_2=\frac{V_2T_1}{V_1}=\frac{1.00L*293K}{2.00L}\\\\T_2=146.5K[/tex]
Thus, the temperature change would be:
[tex]\Delta T=T_2-T_1=146.5K-293K\\\\\Delta T=-146.5K[/tex]
Best regards!
Esters are formed from the reaction of an alcohol and a carboxylic acid. Identify the alcohol and carboxylic acid combination necessary to make each pictured ester.
Answer:
In this practical, students explore the formation of esters through the ability of different alcohols to react with organic acids. Together, the class can quickly produce a range of esters on a test tube scale, with a variety of interesting smells to sample and compare
The pictured ester can be prepared by the combination of ethanol and propionic Acid. The name of the ester in the picture will be ethyl propanoate.
What are esters?Chemicals called esters are created when an oxoacid reacts with a hydroxyl molecule, such as alcohol or phenol. Esters are widely used. The fatty acid esters of glycerol are the majority of naturally occurring fats and oils.
When an ester reacts with either an amine or alcohol, the reaction is referred to as aminolysis; when an ester reacts with water, it is referred to as hydrolysis of ester. Esters are primarily utilized in flavorings and fragrances, but they can also be employed as solvents in the chemical industry.
Therefore, ethanol and propionic acid can be combined to create the ester shown.
To learn more about esters, refer to the link:
https://brainly.com/question/28203011
#SPJ2
The question is incomplete. Your most probably complete question is given below:
The image of the ester is attached below
Which of the following best explains why Reggie's books fell?
Explanation:
When Reggie's car turned eastward, his books continued heading northward, causing them to slide off the top of his car and fall.
were is the opshons.
the reaction between potassium metal and water produces potassium hydroxide and hydrogen gas.
the correct equation for this reaction is:
A: K + H2O—> KOH + H2
B: K + H2O—>KOH + H
C: 4K + 3H2O—> 4KOH + 2H
D: 2K + 2 H2O—> 2KOH + H2
Answer:
2K + 2H₂O → 2KOH + H₂
Explanation:
The reactants are:
Potassium metal = K
Water = H₂O
The products are:
Potassium hydroxide = KOH
Hydrogen gas = H₂
The reaction equation is given as;
Reactants → Products
2K + 2H₂O → 2KOH + H₂
The reaction is a single displacement reaction
how long does crushed candy dissolve in a warm water
Answer:
Because of reaction between solid and liquid
Answer:
shouldn't take that long i would say from 30 to 40 minutes bc its melting in warm water its turning from a solid to a liquid.
Explanation:
Imagine an alternate universe where the value of the Planck constant is 6.6207 x 10^-36 J*s.
In that universe, which of the following objects would require quantum mechanics to describe, that is, would show both particle and wave properties? Which objects would act like everyday objects, and be adequately described by classical mechanics?
3.A turtle with a mass of 450. g, 29. cm long, moving at 2.7 cm/s.
quantum or classical?
Answer:
See explanation
Explanation:
According to Louis de Broglie, particles could exhibit wavelike properties and have an associated wavelength.
Now for a turtle with a mass of 450. g, 29. cm long, moving at 2.7 cm/s, recall that we can only describe a by quantum mechanics when the body is very small and its associated wavelength is large.
This object has a large mass, hence it is discussed by classical rather than quantum mechanics
How many lead atoms in Pb(OH) 4 ?
4 in hydrogen 4 in oxygen
Explanation:
hope this helps
Compounds
are the same as molecules
have the same properties as the elements they are made from
have different properties from the elements they are made from
can only exist as solids or liquids
Answer:
have different properties from the elements they are made from
Explanation:
Compounds have different properties from the elements they are made from. Compounds are substances composed of two or more kinds of atoms/elements joined together in a definite grouping.
The properties of a compound are distinct and different from those of the individual elements that are combined in its make-up. There are several millions of compounds that are known. These are derived from elements.Answer:
Que?
Explanation:
What is the mass number of an atom containing 4 protons and 5 neutrons