Answer:
There are four stages in the metamorphosis of butterflies and moths: egg, larva, pupa, and adult.
Hope this helps :)
Magnesium reacts with sodium fluoride to produce sodiunfluoride and elemental sodium.
Explanation:
Mg+NaF. NaF+Mg
are use sure about the question
A student walks 15 km in 3 hours. What is the student’s average speed?
A :45 km/h
B :5 km/h
12 : km/h
18 : km/h
Answer:
5 km/h
Explanation:
divide the hours to the distance
An ionic bond is a bond between _____.
Answer:
An ionic bond is a bond between two ions of opposite charge (a cation (+) and an anion (-).
Explanation:
I really hope this helps! :)))
Pleas help!! ASAP
Explain the physical and chemical properties of water, including its different phase changes. Why is water so crítical for human life? Written as an paragraph/essay
Explanation:
physical properties of water
Water is a colourless and tasteless liquid. The molecules of water have extensive hydrogen bonds resulting in unusual properties in the condensed form. This also leads to high melting and boiling points. As compared to other liquids, water has a higher specific heat, thermal conductivity, surface tension, dipole moment, etc. These properties form the reason for its significance in the biosphere. Water is an excellent solvent and therefore it helps in the transportation of ions and molecules required for metabolism. It has a high latent heat of vaporization which helps in the regulation of body temperature.
______________________________________
Chemical properties of water
Water reacts with a lot of substances to form different compounds. Some significant reactions are as follows:
Amphoteric nature:
Water can act as both acid and base, which means that it is amphoteric in nature.
Example:
Acidic Behaviour: H2O(l)+NH3(aq) ⇌ H3O+(aq)+NH+4(aq)
Basic Behavior: H2O(l)+H2S(aq) ⇌ H3O+(aq)+HS−(aq)
Redox reactions:
Electropositive elements reduce water to hydrogen molecule. Thus, water is a great source of hydrogen. Let us see an example in this case:
2H2O(l)+2Na(s)→2NaOH(aq)+H2(g)
During the process of photosynthesis, water is oxidized to O2. As water can be oxidized and reduced, it is very useful in redox reactions.
Hydrolysis reaction
Water has a very strong hydrating tendency due to its dielectric constant. It dissolves many ionic compounds. Some covalent and ionic compounds can be hydrolyzed in water
__________________________________
Water is so critical for human life Because...
Water’s extensive capability to dissolve a variety of molecules has earned it the designation of “universal solvent,” and it is this ability that makes water such an invaluable life-sustaining force. On a biological level, water’s role as a solvent helps cells transport and use substances like oxygen or nutrients. Water-based solutions like blood help carry molecules to the necessary locations. Thus, water’s role as a solvent facilitates the transport of molecules like oxygen for respiration and has a major impact on the ability of drugs to reach their targets in the body.
The table shows the average distance between the molecules of a substance in the solid, liquid, and gaseous states.
Distance Between Molecules
State Distance
X 10−9 cm
Y 10−11 cm
Z 10−7 cm
Which of the following is the correct order of the relative strengths of the intermolecular forces in the three states?
Y > Z > X
Z > X > Y
X > Z > Y
Y > X > Z
Answer:
Y > X > Z
Explanation:
The intermoecular forces refer to forces that exist between molecules of a substance. They are the secondary bond forces that hold particles of a substance together in a particular state of matter.
The shorter the distance between molecules, the greater the magnitude of intermolecular force between the molecules.
The molecules of Y are at the shortest distance from each other hence they have the highest magnitude of intermolecular forces. Followed by X and lastly Z with the greatest distance between the largest intermolecular distance.
The energy transformations shown below document the
changes that are a part of what energy resource?
Kinetic --> Mechanical --> Electrical
Solar Enega
Nuclear Energy
o Wind Energy
Fossil Fuels
Which one of the following is most likely to be an ionic compound? SO2
Answer:
Ionic compounds generally form between elements that are metals and elements that are nonmetals. For example, the metal calcium (Ca) and the nonmetal chlorine (Cl) form the ionic compound calcium chloride (CaCl2). In this compound, there are two negative chloride ions for each positive calcium ion
A vessel of volume 100ml contains 10% of oxygen and 90% of an unknown gas. The gases diffuses in 86 second through a small hole of vessel.
If pure oxygen under similar
conditions and diffuses in 75 second, find the molecular weight of unknown gas?
The molecular weight of unknown gas : 23.46 g/mol
Further explanationGiven
A vessel contains 10% of oxygen and 90% of an unknown gas.
diffuses rate of mixed gas = 86 s
diffuses rate of O₂ = 75 s
Required
the molecular weight of unknown gas (M)
Solution
The molecular weight of mixed gas :(M O₂=32 g/mol)
[tex]\tt 0.1\times 32+0.9\times M=3.2+0.9M[/tex]
Graham's Law :
[tex]\tt \dfrac{r_{O_2}}{r_{mixed~gas}}=\sqrt{\dfrac{M_{mixed}}{M_{O_2}} }\\\\\dfrac{75}{86}=\sqrt{\dfrac{3.2+0.9M}{32} }\\\\0.76=\dfrac{3.2+0.9M}{32}\\\\24.32=3.2+0.9M\\\\21.12=0.9M\rightarrow M=23.46~g/mol[/tex]
I REALLY NEED HELP can someone help me please I’ll make you brainliest ! :)
Answer:
C
Explanation:
All thing in option c is flammable
Answer:
D
Explanation:
What type of resource are fossil fuels such as coal, oil, and natural gas?
They are non-renewable resources that formed when prehistoric plants and animals died and were gradually buried by layers of rock.
24. H.SO, has
a) Ionic bond
b) both lonic and covalent bonds
c) ionic covalent and coordinate bonds
d) covalent bond
Answer:
b
Explanation:
Both ionic and covalent bonds when it has dissolved into water it will become ionic compound but when it was in gas situation it was covalent compound.
write an ionic equation for the reaction of nitric v acid and solid carbonate
Answer:
[tex]CO3^{2-}[/tex] + [tex]2H3O^{+}[/tex] => [tex]2H2O[/tex] + [tex]CO2[/tex]
Explanation:
Nitric acid reacts with sodium carbonate to form sodium nitrate, carbon dioxide and water.
Sodium carbonate + nitric acid => sodium nitrate + water + carbon dioxide
2HNO3 + Na2O3 => 2NaNO3 + CO2 + H2O
So the net ionic equation is as follows:
[tex]CO3^{2-}[/tex] + [tex]2H3O^{+}[/tex] => [tex]2H2O[/tex] + [tex]CO2[/tex]
The sodium ion and the nitrate ions are not involved in the net equation because they are not changed in the reaction.
What are some examples of HIGH resistance? Question 2 options: wide wire, short wire, less resistors narrow wire, less resistors, long wire long wire, wide wire, more resistors long wire, narrow wire, more resistors
Answer:
The answer is long wire, narrow wire, more resistors
Explanation: I just took the test and it's right.
burning magnesium is introduced into steam
Answer:
It produces magnesium oxide and hydrogen gas.
Explanation:
When magnesium burns with steam it produces magnesium oxide which is white in color and hydrogen gas. When magnesium burns, it mixes with the oxygen present in the air produces magnesium oxide in powder form. Magnesium react with oxygen by giving two electrons present in its valance shells while the oxygen needs two electron for completing their valance shell and becomes stable.
2. Classify each of these species as a Brønsted acid
ør
base, or both:
(a) H20, (b) OH-(c) H3O+d) NH3, (e) NH..
(f) NH, (g) NO, (h) CO2 (1) HBr, j) HCN
According to Bronsted lowry, the chemical species that donate H+ ions is called acid, and the one that accepts it is called a base.
So here:
Bronsted acids are H3O+, NH4+, HBr, and HCN.
Bronsted bases are : OH- , NH2- , NO3- ,CO32-
Both: H2O, and NH3.
Substances that accept protons from other substances are called Bronsted bases. HCl is a Bronsted-Lowry acid because it is a proton donor, and H2O is a proton acceptor and Bronsted-Lowry base. Consider the example of hydrochloric acid HCl reacting with basic ammonia NH3. In this reaction, HCl donates its proton to NH3.
Therefore, HCl is a Bronsted-Lowry acid. NH3 is a Bronsted-Lowry base because it has a lone pair of electrons that it uses to accept a proton. Ammonia, NH3, is a Lewis base and has a lone pair of electrons. Donates electrons to compounds that accept electrons. NaOH is both an Arrhenius base and a Bronsted-Lowry base. Arrhenius bases are substances that generate OH^ ions in aqueous solutions, and NaOH does this. Bronsted-Lowry bases are proton-accepting substances.
Learn more about Bronsted acids here:-https://brainly.com/question/12377772
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What is the molality of a solution of 10 g NaOH in 500 g water?
Molar mass NaOH = 40 g
Explanation:
Moles of NaOH = 10g / (40g/mol) = 0.25mol.
0.25mol / 500g = 0.50mol / 1000g = 0.50mol/dm³.
The molarity is 0.50mol/dm³.
Write a balanced chemical equation that shows the formation of 2,3-dimethyl-1-butanol from the elements carbon (C), hydrogen (H2 ), and oxygen (O2 ). (Use the smallest integer coefficients possible and do not include states. Enter the elements in the order: C, H, then O in the product box.)
Answer:
12C + 14H₂ + O₂ = 2C₆H₁₃OH .
Explanation:
2,3-dimethyl-1-butanol
= CH₃-CH(CH₃)-CH(CH₃)-CH₂OH.
Molecular formula = C₆H₁₃OH .
= C₆H₁₄O
12C + 14H₂ + O₂ = 2C₆H₁₃OH .
____describes a
solution in which the amount of
solute dissolved in a given amount
of solvent is less than
the solubility limit.
A. Soluble
B. Supersaturated
C. Saturated
D. Unsaturated
SO2Cl2 rightarrow SO2 (g) + Cl2 (g)At 600 K, SO2Cl2 will decompose to form sulfure dioxide and chlorine gas via the above equation. If the reaction is found to be first order overall, which of the following will cause an increase in he half life of SO2CL2?A. Increasing the initial concentration of SO2,CI2.B. Increasing the temperature at which the reaction occurs.C. Decreasing the overall pressure in the container.D. None of these will increase the half life.
Answer: D. None of these will increase the half life.
Explanation:
Half life is the amount of time taken to decay to half of its original value. The half life is related to rate constant by the following relation for a first order reaction:
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
As half life is independent of concentration , temperature and pressure, none of these factors would affect the half life.
Thus in the reaction, [tex]SO_2Cl_2 \rightarrow SO_2(g)+Cl_2(g)[/tex] following first order kinetics, none of the factors will increase the half life.
Adenosine triphosphate is the energy source for work in the cell. It provides energy to the cell and ?
A. deactivates compounds for some reactions by transferring a phosphate group.
B. transfers its adenosine group to DNA.
C. activates compounds for some reactions by transferring a phosphate group.
D. activates enzymes by transferring phosphate groups to change the shape of the enzyme. lol
Answer:
C. activates compounds for some reactions by transferring a phosphate group.
Explanation:
Adenosine triphosphate, also known as ATP, is an energy carrier molecule used by the cells of living organisms to carry out their cellular function. ATP has the peculiar ability to store and release energy needed to do work. This energy is stored when a phosphate molecule is added to ADP to form ATP while it is released when the last phosphate group is removed to form ADP.
ATP supplies energy to compounds by transferring one of its phosphate molecules to it in a process called PHOSPHORYLATION. This transfer causes the compound to be activated for the cellular process it is about to undergo.
Dentify the compound in each of the following pairs that reacts with sodium iodide in acetone at the faster rate:__________. (a) 1-Chlorohexane or cyclohexyl chloride (b) 1-Bromopentane or 3-bromopentane (c) 2-Chloropentane or 2-fluoropentane (d) 2-Bromo-2-methylhexane or 2-bromo-5-methylhexane (e) 2-Bromopropane or 1-bromodecane
Answer:
a) 1-Chlorohexane
b) 1-Bromopentane
c) 2-Chloropentane
d) 2-bromo-5-methylhexane
e) 1-bromodecane
Explanation:
One important fact that we must have behind our minds as we approach the problem is the fact that sodium iodide in acetone will lead to an SN2 reaction because the nucleophile (iodide ion) is naked and not solvated. Also, the iodide ion is a good nucleophile and the solvent is a polar aprotic solvent. All these factors together make the reactions to tilt towards SN2 mechanism.
In a) 1-Chlorohexane offers less steric hinderance and more ease of SN2 reaction hence the answer.
In b) 1-Bromopentane offers less steric hinderance being a primary alkyl halide hence the answer.
c) In c) 2-Chloropentane contains chlorine which is more polarizable and a better leaving group than fluorine.
In d) 2-bromo-5-methylhexane is a secondary alkyl halide and undergoes SN2 reaction with less steric hindrance. 2-Bromo-2-methylhexane is a tertiary alkyl halide and does not undergo SN2 reaction due to steric hindrance.
e) 1-bromodecane is a primary alkyl halide and offers less steric resistance to the approaching nucleophile than 2-Bromopropane.
What is used to determine the number of each atom in an ionic formula?
A. The oxidation state of each atom
B. The number of bonds in the formula
C. The electronegativity of each atom
D. The period of the metal in the formula
the oxidation state of each atom
What is the maximum number of electrons that an L shell may contain?
Answer:
Eight
Explanation:
The L shell only holds eight electrons.
8
The L shell can only holds eight electrons
Explain what is meant by a half-life of 150 years. Then, write a function that models the amount, A, of a 100-mg sample remaining after T years for a substance with a half-life of 150 years. Use graphing software to graph the equation. Answer in complete sentences.
Answer:
Half-life of 150 years are those year that a radioactive element take to disintegrate to a half of it's original value.
I don't have graphical software
Suppose a student made a different sodium hydroxide solution using 0.401g of solid sodium hydroxide and 200mL of water. The student then standardized this solution using benzoic acid in a similar manner to that depicted in the simulation. From the following additional data recorded by the student: a) Mass of benzoic acid: 0.158g b) Volumer of the benzoic acid solution: 100.0mL c) Volume of sodium hydroxide need to neutralize the solution: 27.84mL Determine the molarity of the sodium hydroxide solution.
Answer:
0.05 M
Explanation:
Mass of benzoic acid= 0.158g
Volume of benzoic acid= 100 mL
Volume of sodium hydroxide = 27.84mL
Molar mass of benzoic acid= 122g/mol
Number of moles of benzoic acid= 0.158g/122g/mol= 1.3 × 10^-3 moles
C= no of moles/volume
C= 1.3 × 10^-3 moles × 1000/100
C= 0.013M
So;
Volume of acid VA = 100mL
Concentration of acid CA= 0.013M
Volume of Base VB = 27.84mL
Concentration of Base CB= ???
Number of moles of acid NA =1
Number of moles of Base NB= 1
From;
CAVA/CBVB= NA/NB
CAVANB= CBVBNA
CB= CAVANB/VBNA
CB= 0.013 × 100 × 1/27.84 × 1
CB= 0.05 M
Can some one help me plz
Answer:
what does it say its blurry
Explanation:
A certain mass of hydrogen gas collected over water at 10°C and 750mmHg pressure has a volume of 57cm3. Calculate the volume when it is dry at S.T.P ( S.V.P of water at 10°C = 9.2 mmHg .
The volume of gas when it is dry at S.T.P : 53.6 cm³
Further explanationGiven
P tot=750 mmHg
V₁=57 cm³
T₁=10 °C = 283 K
P₂ = 760 mmHg(STP)
T₂ = 273 K(STP)
Required
P dry gas at STP
Solution
Dalton's Law
P tot = P H₂O + P gas
P gas = 750 mmHg - 9.2 mmHg
P gas = 740.8 mmHg = P₁
Combined gas Law
[tex]\tt \dfrac{P_1.V_1}{T_1}=\dfrac{P_2.V_2}{T_2}\\\\V_2=\dfrac{P_1.V_1.T_2}{T_1.P_2}\\\\V_2=\dfrac{740.8\times 57\times 273}{283\times 760}=53.6~cm^3[/tex]
Initial Phenomena Question: Magnesium metal reacts with hydrochloric acid to produce magnesium chloride and hydrogen gas; how can you prove that?
Answer:
See explanation
Explanation:
The reaction equation is as follows;
Mg(s) + 2HCl(aq) -------> MgCl2(aq) + H2(g)
Firstly, the appearance of bubbles of gas shows that a gas is evolved in the reaction.
Secondly, If we hold up the flame of a butane fireplace lighter above the appearing hydrogen bubbles, we will hear audible pops as the hydrogen gas ignites showing that a combustible gas is produced in the reaction.
Lastly, as the reaction proceeds, the magnesium ribbon disappears as MgCl2 is formed. If a set up such as the image attached is used, hydrogen gas is collected over water.
Image credit: RSC education
Which of the following is a chemical property?
O volume
O flammability
O color
O weight
Answer:
your answer is flammability
Ralph conducted an experiment to study the effect of temperature change on the heart rate of
Daphnia, transparent aquatic invertebrates commonly known as water fleas. Ralph heated three
different beakers of water containing Daphnia to a different temperature: 30°C, 32°C, and 34°C.
He put a drop of water from each beaker on a slide mount. He then used a microscope to observe
Daphnia in each sample. He counted the number of heartbeats in one minute and averaged his
results. Which of the following could be a step in a replication of this experiment?
Answer:
c. Ralph's classmate observing Daphnia in water at 30oC, 32oC and 34oC
Explanation:
When we talk about replication, we actually mean, repetition of a scientific procedure carried out by another scientist and obtaining the same results as he/she previously did.
Replication is carried out under identical conditions as the first scientist did. If Ralph's classmate wants to replicate Ralph's work, then identical temperature conditions of 30oC, 32oC and 34oC must be used, hence the answer above.