Answer:
A. AgNO3
I hope it's helps
What does a high boiling point temperature indicate about a substance?
A. Little heat has been added to the system.
B. Intermolecular forces are hard to overcome.
C. Chemical bond energy is very high.
D. The pressure over the liquid is very low.
Answer:
B. Intermolecular forces are hard to overcome
Explanation:
A high boiling point indicates greater inter molecular forces between the molecules of the substance. Inter molecular forces is the force of attraction between the molecules of the substance, which has to be overcome or broken before the substance boils. Example, when water boils, the water molecule (H₂O) will be broken into hydrogen molecule and oxygen molecule.
Therefore, a high boiling point temperature indicates that intermolecular forces of the substance are hard to overcome.
B. Intermolecular forces are hard to overcome
Answer:
b
Explanation:
Question 28 (2 points)
Which of the following is part of the Kinetic Molecular Theory?
1) gases consist of tiny particles that are close together
2) gas molecules are in constant random motion
3) Il of the above are part of the Kinetic Molecular Theory
4) the average kinetic motion of gas molecules decreases with an increase in
temperature
Marook nie
Answer:
Il of the above are part of the Kinetic Molecular Theory
Explanation:
Answer: Which of the following are part of kinetic-molecular theory?
Choices:
1. The particles in a solid do not move.
2. The particles in a liquid are moving past one another constantly.
3. The particles in gas move freely in all directions.
4. The particles in a solid vibrate in a fixed position.
5. The particles in a solid are far apart.
6. The particles in a gas have few attractions between them.
7. The particles in all states of matter are always moving.
Explanation: Which of the following are part of kinetic-molecular theory...
Answers:
2. The particles in a liquid are moving past one another constantly.
3. The particles in gas move freely in all directions.
4. The particles in a solid vibrate in a fixed position.
6. The particles in a gas have few attractions between them.
7. The particles in all states of matter are always moving.
Zinc will displace copper from a solution of copper sulfate, and magnesium will displace zinc from a solution of zinc sulfate. Why can these displacement reactions be regarded as redox reactions? Write down a series of reactivity for these three metals, putting them in order of increasing reactivity.
Answer:
The displacement reactions are regarded as redox reactions because they involve the formal transfer of electrons from one chemical specie to the other
2) The series of reactivity of the metals in the order of increasing reactivity are;
Copper↓
Zinc↓
MagnesiumExplanation:
1) Redox (oxidation-reduction) reaction is a chemical reaction involving the loss and gain of electrons from one chemical species to another, where the chemical species that undergoes oxidation, loses electrons and is termed the reducing agent, while the other chemical species that undergoes reduction, gains electrons, and is termed the oxidizing agent
2) The redox reaction can being based on the affinity for electrons depends on the positions of the reactants in the electrochemical series as well as the chemical reactivity of the metals with zinc being a stronger reducing agent and more chemically reactive than copper and magnesium being a stronger reducing agent and more chemically reactive than zinc
Least reactive (Cu) < (Zn) < Mg Most reactive
Copper < Zinc < Magnesium.
What is the concentration of iodine molecules, I 2 in a solution containing 2.54g of iodine in 250 cm 3 of solution?
Answer:
) Molar concentration =1000*2.54/(127*250) ;since molarity=1000*W/M*V
=0.08 M here W=amount of solute in gm
M= molecular weight of solute
v=volume of solution in ml or cm3
2)% concentration (w/v) =(2.54/250)*100=1.016%
Explanation:
What is the pH of a 0.45 M solution of hydrochloric acid
pH = 0.35
Explanation: hope this helps
Answer: 0.35
Explanation:
what is genetic tagging
Answer:
Genetic tagging, or the identification and tracking of individual animals using DNA, is a non-invasive method of conducting research that uses samples from shed hair, feathers, feces, or saliva. ... Genetic tagging approaches are complementary to traditional approaches and add a powerful tool to the ecologists' toolkit."
Explanation:
sperm can be carried by _____ grains. ANSWERSSSSSSSSSSSSSSSSS O spore O stamen O pollen
What is pollen in the reproduction cycle of flowering plants?
A pollen grain is a microspore containing the male gametophyte, usually reduced to two undivided cells, each with one haploid (n) nucleus. These cells are surrounded by a very resistant wall, the exine, which generally has apertures, zones with less resistance which will allow the germination of the pollen tube.
Explanation of the reproduction cycle (cf diagram above)
A given species produces flowers bearing stamens. According to species, these flowers can be unisexual (stamens only) or bisexual (stamens and carpels).
The stamen anthers include 4 pollen sacs containing sporogenous cells (diploid=2n). These sporogenous cells undergo meiosis, each producing 4 microspores (haploid=n). Two nuclei are then formed by mitosis : the vegetative nucleus and the generative nucleus. The latter divides to form 2 sperms. Simultaneously the wall of the microspores becomes thicker and takes the characteristic shape of the species : it is a pollen grain (see: What are the morphological characteristics of pollen and spore grains?). In the majority of species, the 4 grains (resulting from the 4 microspores) split up into single grains; in some cases, they remain together (tetrad = group of 4 grains). When mature, pollen grains are released by the opening of the anthers.
A pollen grain is aimed at reaching another flower of the same species, bearing carpels. The ovaries contain ovules, in which meiosis occurs, then mitoses. It results in an embryo sac with 8 nuclei, among which an egg cell and 2 central cells. When a pollen grain arrives on another flower (see : How are the spores and pollen grains transported?), it is received by the stigmas.
The pollen grain germinates through an opening of the wall: the vegetative nucleus develops into a pollen tube which is guided by the style to the ovary, then enters the micropyle of an ovule. The pollen tube releases 2 sperm nuclei into the ovule: one of the sperms fuses with the egg cell into a zygote (2n), while the other sperm fuses with central nuclei and gives rise to albumen (= food source). There are generally several ovules in an ovary : each one can be fertilized by a distinct pollen grain.
Each fertilized ovule and its albumen form a seed that will develop into a new individual of this species. hope it works
Answer:
pollen
Explanation:
you insolent vacuum
On many common appliances, there is an “O” or “I” on the power switch. What does each symbol mean?
Mendeleev's periodic table of elements was created in 1901.
O A. True
O B. False
Explanation:APΕX
Please help me with number 12
Answer:
organisms in rain water and the number of organisms in pond water because the dependant variable never changes
Explanation:
because the dependant variable never changes
In the equation E = mc2, what does c represent?
Answer:
c is the speed of light
Explanation:
E: energy
m: mass
c2: speed of light squared
Predict the arrangement of the following substances in decreasing order of pH value Orange juice || Bitter gourd juice || Hydrochloric acid || Mineral water
Answer:
Mineral water> Bitter gourd juice> Orange juice> Hydrochloric acid
Explanation:
pH is referred to as the degree of acidity or alkalinity of a substance. The pH scale is arranged from 0-14. Substance with a pH of 0-6.9 are acid, a pH of 7 indicates neutrality while a pH of 8-14 indicates alkalinity.
Mineral water is usually slightly acidic with a pH between 5-6. The pH of bitter gourd juice is between 4.24-4.45. The pH of orange juice ranges between 3.3 to 4.2 lastly, the pH of hydrochloric acid is about 3.01.
The pH values itemized above informed the arrangement of decreasing pH values shown in the answer box.
pls help me 13 min left if you go past and not help are not mine
Answer:
mushroom
mold
spore cases
hyphae
fungus
A sample of wood with a mass of 30 g has its
temperature changed from 10° to 45° C. In the
process, it releases 90 J of heat. What is its specific
heat?
Answer:
0.086J/g°C
Explanation:
The following data were obtained from the question:
Mass (M) = 30g
Initial temperature (T1) = 10°C
Final temperature (T2) = 45°C
Change in temperature (ΔT) = T2 – T1 = 45°C – 10°C = 35°C
Heat (Q) released = 90J
Specific heat capacity (C) of wood =..?
We can obtain the specific heat capacity of the wood as follow:
Q = MCΔT
90 = 30 x C x 35
Divide both side by 30 x 35
C = 90/(30 x 35)
C = 0.086J/g°C.
Therefore, the specific heat capacity of the wood is 0.086J/g°C.
The elements least likely to form bonds are found in which group?
Answer:
Noble gases are a unique set of elements in the periodic table because they don't naturally bond with other elements.
Explanation:
HAVE A GOOD DAY!
Answer:
The answer is Noble Gases!!
Explanation:
Hope i helped yall! Have a super fantastic day!! Play Among Us! (Of course when your done with school) lol, jk, but u can!! Byes yall!
Mention 6 products from coal tar as a result of destructive distillation of coal
Answer:
Coke, coal gas, gas carbon, ammonia liquor, and coal oil
hello can you please help me to solve above questions. .
Answer:
i)a. P & R
b. Q& S
ii) R
iii) Atomic no & Atomic radius
2)a. C4H10
b. CH3Cl
Which answer best describes what is happening in the following redox reaction?
4Fe + 302.
2Fe2O3
Answer:
Iron is oxidized to form rust.
Explanation:
Consider the reaction; 4Fe + 302------>2Fe2O3, we can see that iron is being oxidized to iron III oxide. Rust is the common name of iron III oxide.
Rusting is an electrochemical process, iron rusts when it comes into contact with air and water because electrochemical cells are set up at the surface of contact.
Iron usually functions as the anode in the electrochemical process. This process leads to the formation of iron III oxide. Rust is soft and breaks off easily thereby exposing the metal below the surface to further rusting.
Answer:
Iron is oxidized to form rust.
Explanation:
edge
Pls help asap!!! I don’t understand how to do it
Answer:
split the reaction in to respective ions to ge the ionic equation of this reaction
Explanation:
2 Al + 2Fe+3 O3^-2 ---> 2Al+3 O3^-2 + 2Fe
ins simple it would be
Al + Fe+3 ----> Al+3 + Fe
Formula los siguientes compuesto: Dietil eter, Etanol, Propanotriol, Acido Propanodioico, Pentanal, Pentano-2,4-diona, Metanoato de metilo, Ciclohexano-1,3-diol, Acido heptanoico, Ciclobutil metil éter, acetato de etilo, 2-metilbenzaldehído, Ciclohexanona, Butanona
Answer:
Explanation:
En este caso para formular los compuestos, debes identificar el grupo funcional principal de la molecula. Una vez que eso está hecho, puedes intentar formularlo.
Empezaremos primero identificando el grupo funcional principal de la molécula, para luego formularlo correctamente.
Dietil eter: la terminación eter al final significa que pertenece al grupo de los éteres, el cual tiene como formula general R - O - R.
Etanol: debido a que termina en ol, este grupo pertenece a los alcoholes. Para formularlo solo se dibuja la molecula del etano, junto a un enlace con el grupo OH, como su formula general R - OH.
Propanotriol: igualmente termina en ol, por lo tanto es un alcohol, sin embargo, en este caso, tambien tiene la terminación prefija tri, asi que significa que hay 3 grupos OH en la molecula.
Acido propanodioico: esta es sencilla, porque empieza como acido, y solo hay un grupo funcional que empieza así y son los acidos carboxilicos, es decir, el grupo COOH (R - COOH) que es el carboxilo. Tiene el prefijo di, antes del oico, por lo que son dos carboxilos presentes en la molecula.
Pentanal: el sufijo al, significa que pertenece al grupo de los aldehidos, en este caso, posee el grupo carbonilo H - C = O.
Pentano - 2,4 - diona: la terminación ona significa que pertenece al grupo de las cetonas, (R - CO - R), parecido a los aldehidos, con la diferencia de que tiene grupos alquilos en lugar de un hidrogeno.
Metanoato de metilo: la terminación ato de ilo, pertenece a los esteres, (R - COOR) derivado de los acidos carboxilicos.
De aqui en adelante solo mencionaré los grupos funcionales pues ya se explicó el por que, por sus terminaciones:
Ciclohexano - 1.3 - diol: este pertenece a los alcoholes.
Acido heptanoico: acido carboxilico
Ciclobutil metil eter: eteres
Acetato de etilo: ester
2-metilbenzaldehído: aldehído unido a un grupo aromatico como el benceno.
Ciclohexanona: un ciclo (cadena cerrada) unido a un grupo carbonilo.
Butanona: cetona.
Observa la foto adjunta para que veas la formulación de cada una:
Diphosphorus pentoxide(P2O5) reacts with water to form phosphoric acid, a major industrial acid. In the laboratory, the oxide is used as a drying agent. a.What is the mass of 4.65 x 10 22molecules of phosphorus pentoxide?
Answer: The mass of [tex]4.65\times 10^{22}[/tex] molecules of phosphorus pentoxide is 20.5 g
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to the molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given molecules}}{\text {avogadro's number}}=\frac{4.65\times 10^{22}}{6.023\times 10^{23}}=0.0772moles[/tex]
1 mole of [tex]P_2O_5[/tex] weigh = 283.9 g
Thus 0.0772 moles of [tex]P_2O_5[/tex] weigh = [tex]\frac{283.9}{1}\times 0.0722=20.5g[/tex]
Thus the mass of [tex]4.65\times 10^{22}[/tex] molecules of phosphorus pentoxide is 20.5 g
A gas sample that has a pressure of 4.23 atm, a volume of 1,870 mL, and a temperature of 293 K is allowed to expand to a volume of 6.01 L with a final temperature of 373 K. What is the final pressure of the gas in atmospheres?
Answer:
1.68 atm.
Explanation:
Given:
P1 = 4.23atm
V1 = 1870 mL
T1 = 293K
P2 = ?
V2 = 6.01 L = 6010 mL
T2 = 373 K
Assuming number of moles and R is constant:
[tex]\frac{P1V1}{T1} = \frac{P2V2}{T2}[/tex]
⇒ P2 = [tex]\frac{P1V1T2}{T1V2}[/tex] = [tex]\frac{2,950,467.3}{1,760,930}[/tex]
= 1.68 atm.
Tom has 1 cup of a 5% vinegar-water solution, 2 cups of a 10% vinegar-water solution, and 3 cups of a 15% vinegar-water solution. He needs at least 8 cups of a 5% vinegar-water solution for his chemistry project. What is the number of cups of pure water he should add to the total of all his vinegar-water solutions to complete the project?
Answer:
Another eight cups of pure water will be required.
Explanation:
Start by calculating the amount (in cups) of vinegar in these six cups:
One cup of [tex]5\%[/tex] vinegar-water solution would contain [tex]0.05[/tex] cups of vinegar.Two cups of [tex]10\%[/tex] vinegar-water solution would contain [tex]2 \times 0.10 = 0.20[/tex] cups of vinegar.Three cups of [tex]15\%[/tex] vinegar-water solution would contain [tex]3 \times 0.15 = 0.45[/tex] cups of vinegar.Therefore, if these six cups of solutions were mixed, the mixture would contain [tex]0.05 + 0.20 + 0.45 = 0.70[/tex] cups of vinegar. Also, the mixture is supposed to have a volume of six cups. Therefore, the concentration of this six-cup mixture would be:
[tex]\displaystyle \frac{0.70\; \rm cups}{6\; \rm cups} \approx 12\%[/tex].
In other words, if these six cups of vinegar-water solutions are mixed, it would be necessary to dilute (by adding more water) before reaching the concentration of [tex]5\%[/tex].
The goal is to dilute this solution with [tex]0.70[/tex] cups of vinegar to a concentration of [tex]5\%[/tex]. Consider: what would be the volume the solution after dilution?
The volume of a solution can be found from the quantity and concentration of its solute:
Quantity of vinegar in this solution: [tex]0.70[/tex] cups.Concentration of vinegar in this solution: [tex]5\% = 0.05[/tex].After dilution, the volume of this solution would be:
[tex]\displaystyle \frac{0.70\; \rm cups}{0.05} = 14\; \rm cups[/tex].
At this moment, this solution only has a volume of six cups. Therefore, [tex]14 - 6 = 8[/tex] cups of pure water will be required.
Identify the following as an example of a physical or chemical. Olive oil, vinegar, salt, and pepper are shaken together together to make salad dressing
Answer:
Chemical Change
Explanation:
Mixing these elements together creates a chemical change
Making of a salad dressing is a physical change as there is no change in the chemical composition.
What is a physical change?
Physical changes are defined as changes which affect only the form of a substance but not it's chemical composition. They are used to separate mixtures in to chemical components but cannot be used to separate compounds to simpler compounds.
Physical changes are always reversible using physical means and involve a change in the physical properties.Examples of physical changes include melting,boiling , change in texture, size,color,volume and density.Magnetism, crystallization, formation of alloys are all reversible and hence physical changes.
They involve only rearrangement of atoms and are often characterized to be changes which are reversible.
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what mass of methanol is produced when 280.2 g of carbon monoxide reacts with 50.5 g of hydrogen? CO(g)+2H2(g)—> CH3OH(l)
Answer:
320.23g of CH3OH.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
CO(g) + 2H2(g)—> CH3OH(l)
Next, we shall determine the masses of CO and H2 that reacted and the mass of CH3OH produced from the balanced equation. This is illustrated below below:
Molar mass of CO = 12 + 16 = 28g/mol
Mass of CO from the balanced equation = 1 x 28 = 28g
Molar mass of H2 = 2x1 = 2g/mol
Mass of H2 from the balanced equation = 2 x 2= 4g
Molar mass of CH3OH = 12 + (3x1) + 16 + 1 = 32g/mol
Mass of CH3OH from the balanced equation = 1 x 32 = 32g
From the balanced equation above,
28g of CO reacted with 4g of H2 to produce 32g of CH3OH.
Next, we shall determine the the limiting reactant. This is illustrated below:
From the balanced equation above,
28g of CO reacted with 4g of H2.
280.2g of CO will react with =
(280.2 x 4)/28 = 40.03g of H2.
From the calculations made above, we can see that only 40.03g out of 50.5g of H2 is required to react completely with 280.2g of CO.
Therefore, CO is the limiting reactant and H2 is the excess reactant.
Finally, we shall determine the mass of methanol, CH3OH produced from the reaction.
In this case, the limiting reactant will be used because it will give the maximum yield of the reaction since all of it is used up in the reaction. The limiting reactant is CO and the mass of methanol, CH3OH produced can be obtained as follow:
From the balanced equation above,
28g of CO reacted to produce 32g of CH3OH.
Therefore, 280.2g of CO will react to produce = (280.2 x 32)/28 = 320.23g of CH3OH.
Therefore, 320.23g of CH3OH were produced from the reaction.
what happens when sodium and sulfur combine
Answer:
Sodium sulfide is the chemical compound with the formula Na2S, or more commonly its hydrate Na2S·9H2O. Both the anhydrous and the hydrated salts are colorless solids. They are water-soluble, giving strongly alkaline solutions. When exposed to moist air, Na2S and its hydrates emit hydrogen sulfide, which smells like rotten eggs. Some commercial samples are specified as Na2S·xH2O, where a weight percentage of Na2S is specified. Commonly available grades have around 60% Na2S by weight, which means that x is around 3. Such technical grades of sodium sulfide have a yellow appearance owing to the presence of polysulfides. These grades of sodium sulfide are marketed as 'sodium sulfide flakes'.
Contents
1 Structure
2 Production
3 Reactions with inorganic reagents
4 Uses
4.1 Reagent in organic chemistry
5 Safety
6 References
Structure
Na2S adopts the antifluorite structure,[2][3] which means that the Na+ centers occupy sites of the fluoride in the CaF2 framework, and the larger S2− occupy the sites for Ca2+.
Production
Industrially Na2S is produced by carbothermic reduction of sodium sulfate often using coal:[4]
Na2SO4 + 2 C → Na2S + 2 CO2
In the laboratory, the salt can be prepared by reduction of sulfur with sodium in anhydrous ammonia, or by sodium in dry THF with a catalytic amount of naphthalene (forming sodium naphthalenide):[5]
2 Na + S → Na2S
Reactions with inorganic reagents
The sulfide ion in sulfide salts such as sodium sulfide can incorporate a proton into the salt by protonation:
S2−
+ H+ → SH−
Because of this capture of the proton ( H+), sodium sulfide has basic character. Sodium sulfide is strongly basic, able to absorb two protons. Its conjugate acid is sodium hydrosulfide (SH−
). An aqueous solution contains a significant portion of sulfide ions that are singly protonated.
S2−
+ H
2O {\displaystyle {\ce {<=>>}}}{\displaystyle {\ce {<=>>}}} SH−
+ OH−
(1)
SH−
+ H
2O {\displaystyle {\ce {<<=>}}}{\displaystyle {\ce {<<=>}}} H
2S + OH−
(2)
Sodium sulfide is unstable in the presence of water due to the gradual loss of hydrogen sulfide into the atmosphere.
When heated with oxygen and carbon dioxide, sodium sulfide can oxidize to sodium carbonate and sulfur dioxide:
2 Na2S + 3 O2 + 2 CO
2 → 2 Na2CO3 + 2 SO2
Oxidation with hydrogen peroxide gives sodium sulfate:[6]
Na2S + 4 H2O2 → 4 H
2O + Na2SO4
Upon treatment with sulfur, polysulfides are formed:
2 Na2S + S8 → 2 Na2S5
Uses
Sodium sulfide is primarily used in the kraft process in the pulp and paper industry.
It is used in water treatment as an oxygen scavenger agent and also as a metals precipitant; in chemical photography for toning black and white photographs; in the textile industry as a bleaching agent, for desulfurising and as a dechlorinating agent; and in the leather trade for the sulfitisation of tanning extracts. It is used in chemical manufacturing as a sulfonation and sulfomethylation agent. It is used in the production of rubber chemicals, sulfur dyes and other chemical compounds. It is used in other applications including ore flotation, oil recovery, making dyes, and detergent. It is also used during leather processing, as an unhairing agent in the liming operation.
Reagent in organic chemistry
Alkylation of sodium sulfide give thioethers:
Na2S + 2 RX → R2S + 2 NaX
Even aryl halides participate in this reaction.[7] By a broadly similar process sodium sulfide can react with alkenes in the thiol-ene reaction to give thioethers. Sodium sulfide can be used as nucleophile in Sandmeyer type reactions.[8] Sodium sulfide reduces1,3-dinitrobenzene derivatives to the 3-nitroanilines.[9] Aqueous solution of sodium sulfide can be refluxed with nitro carrying azo dyes dissolved in dioxane and ethanol to selectively reduce the nitro groups to amine; while other reducible groups, e.g. azo group, remain intact.[10] Sulfide has also been employed in photocatalytic applications.[11]
Explanation:there you go
When sodium combines with sulphur, it formed sodium sulphide. When it interacts with sulfur, polysulfides are produced. Additionally, heat causes sodium sulfide to oxidize fast. Sulfur dioxide and sodium carbonate are the end products.
What is sulphur ?Chemical element sulfur has the letter S and atomic number 16. It is multivalent, nonmetallic, and plentiful. Sulfur atoms normally combine to create cyclic octatomic molecules, which have the chemical formula S₈.
At room temperature, elemental sulfur is a crystalline solid that is brilliant yellow. It is employed in the production of fertilizer, water treatment, mineral extraction, oil refining, and automobile batteries.
Other uses for compounds based on sulfur include vulcanizing rubber, bleaching paper, and producing goods like cement, detergents, and insecticides.
Thus, When sodium combines with sulphur, it formed sodium sulphide.
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16. State one advantage and disadvantage
of rusting
Answer:
Advantage:
It forms ferrous oxide which is used as a pigment for glasses
Disadvantage:
It destroys the appearance of the metal and weakens it.
Answer:
Advantage: Rusting provides a thin durable shell to prevent the metal from getting more corroded.
Disadvantage: Rusting weakens material due to prolonged corrosive action.
Explanation:
The mass number of Fo? is 56. How many neutrons are there in a single Fo? atom?
28
30
56
58
Answer: A. 28
If we aren't talking about an isotope, then the number of neutrons and the number of protons in the nucleus are the same. Each proton weighs one atomic unit, and the same can be said about a neutron as well. So half of the weight is from the protons and half is from the neutrons. The electrons are extremely small relative to the protons that their weight is negligible.
What is the molecularity of the elementary step A+ B+ C?
O A.
unimolecular
OB.
bimolecular
O C. trimolecular
OD
tetramolecular
Answer:
trimolecular
Explanation:
In order to answer this question, you need to look around your immediate surroundings to find examples of rusting of iron or any other metal. i. What makes iron rust? ii. Why is the rusting of iron a problem? Give any 3 examples from daily life where rusting has been a disadvantage. iii. Suggest any two ways that can help prevent rusting of iron.
Answer:
(i) rusting is caused by the reaction of oxygen and water on the surface of metals(iron).
(ii) rusting of iron makes it weak and dangerous for buildings since their foundation is made of iron, rusting renders cars useless, rusting can cause accidents.
(iii) by galvanizing iron
and by coating it.
Explanation:
hope it helps .