Answer:
0.017 mole of Pb(NO₃)₂.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2KOH + Pb(NO₃)₂ —> 2KNO₃ + Pb(OH)₂
From the balanced equation above,
1 mole of Pb(NO₃)₂ reacted to produce 2 moles of KNO₃.
Finally, we shall determine the number of mole of Pb(NO₃)₂ required to produce 0.034 mole of KNO₃. This can be obtained as follow:
From the balanced equation above,
1 mole of Pb(NO₃)₂ reacted to produce 2 moles of KNO₃.
Therefore, Xmol of Pb(NO₃)₂ will react to produce 0.034 mole of KNO₃ i.e
Xmol of Pb(NO₃)₂ = 0.034 / 2
Xmol of Pb(NO₃)₂ = 0.017 mole.
Thus, 0.017 mole of Pb(NO₃)₂ is needed for the reaction.
What is the balanced chemical equation for silicon + oxygen?
Answer:
SiO2
Explanation:
Si + O2 → SiO2
Classify the following amine as 1º, 2º, 3º or 4°
(primary, secondary, tertiary, quaternary).
(CH3)4N+
A. primary
B. secondary
D. quarternary
C. tertiary
Answer:
D. Quaternary
Explanation:
I'm going to attach a picture that can help you understand how amines are classified!
I'll explain how amines are classified below. You can skip it if you feel that you already understand that!
--------------------------------------------------------------------------------------------------------------
So we know that amines are composed of nitrogen, at least one R group, and hydrogens. The way that we categorize amines as primary, secondary, tertiary, or quarternary is by counting the number of R groups.
Now, how do we identify the R groups?
Well, basically anything that isn't a hydrogen. You will see that the nitrogen in an amine standardly only makes 3 bonds. If all those three bonds are with a hydrogen, then it will be ammonia. If it is a primary amine, then one of those hydrogens will be replaced with another compound (like [tex]CH_{3}[/tex] in this case). This other compound is called an R group. R groups will change based on the amine. A secondary amine will have two hydrogens replaced with groups. A tertiary amine will have all three hydrogens replaced with R groups.
--------------------------------------------------------------------------------------------------------------
Now, by this logic, we can just count the number of R groups in [tex](CH_{3} )_{4} N^{+}[/tex] and we should get our answer! We don't see any hydrogens. That means we can immediately rule out both A. and B.
Well, let's see. It looks like [tex]CH_{3}[/tex] is our R group. The subscript for it is also 4.
But we've used up our 3 bond spots, how is a quaternary amine possible? And that is why you see that your nitrogen has a positive charge in [tex](CH_{3} )_{4} N^{+}[/tex]. Since the nitrogen is bonded with more groups than it usually does, the electrons of nitrogen and therefore the electrical charge will be shared between more compounds and elements, leading to less charge for the nitrogen. This will cause it to have a positive charge. Making your amine an ion will allow for 4 bonds.
That is why even though nitrogen usually only has 3 bonds, we can still classify [tex](CH_{3} )_{4} N^{+}[/tex] as a quaternary amine.
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The last part got a little lengthy, but I hope I was able to explain this question in-depth! If you had any trouble understanding what I wrote, feel free to leave a comment. I will reply as soon as possible!
Calculate the hydrogen ion concentration in a 3.4 x 10-3 M
solution of KOH.
Explanation:
[tex]KOH→K {}^{ + } + OH {}^{ - } \\ [OH {}^{ - } ] = 3.4 \times {10}^{ - 3} \\ k _{w} = [OH {}^{ - } ] [H {}^{ + } ] \\ 1 \times {10}^{ - 14} = 3.4 \times {10}^{ - 3} \times [H {}^{ + } ] \\ [H {}^{ + } ] = 2.94 \times {10}^{ - 12} \: M[/tex]
Answer:
2.9 X 10^-12 M
Explanation:
The picture shows a plant that lives in Florida.
This plant lives in other parts of the United States, too. It has a longer growing season in Florida than it does in northern areas of the country,
Which sentence best describes how Florida's warmer weather and longer growing season will affect this plant?
A. It will lose its leaves much sooner than northern plants.
B. It will produce fewer flowers than northern plants.
C. It will not be able to migrate like northern plants.
D. It will have a much shorter dormant period than northern plants.
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Answer:
I think its D. Sorry if I'm wrong
Explanation:
Combustion of 1.125 of an unknown compound containing carbon, hydrogen, and oxygen resulted in 1.649g of CO2 and 0.675g of H2O. If the molar mass is 180g/mol What is the molecular formula?
CxHyOz + O2 → CO2 + H2O
The molecular formula of the unknown compound, given that it contains carbon, hydrogen, and oxygen is C₆H₁₂O₆
How do I determine the molecular formula?First, we'll begin by obtaining the mass of carbon, hydrogen and oxygen. Details below:
For Carbon
Mass of CO₂ = 1.649 gMolar mass of CO₂ = 44 g/mol Molar of C = 12 g/mol Mass of C =?Mass of C = (12 / 44) × 1.649
Mass of C = 0.45 g
For Hydrogen
Mass of H₂O = 0.675 gMolar mass of H₂O = 18 g/mol Molar of H = 2 × 1 = 2 g/mol Mass of H =?Mass of H = (2 / 18) × 0.675
Mass of H = 0.075 g
For Oxygen
Mass of compound = 1.125 gMass of C = 0.45 gMass of H = 0.075 gMass of O =?Mass of O = (mass of compound) - (mass of C + mass of H)
Mass of O = 1.125 - (0.45 + 0.075)
Mass of O = 0.6 g
Next, we shall determine the empirical formula. details below:
C = 0.45 gH = 0.075 gO = 0.6 gEmpirical formula =?Divide by their molar mass
C = 0.45 / 12 = 0.0375
H = 0.075 / 1 = 0.075
O = 0.6 / 16 = 0.0375
Divide by the smallest
C = 0.0375 / 0.0375 = 1
H = 0.075 / 0.0375 = 2
O = 0.0375 / 0.0375 = 1
Thus, the empirical formula of the compound is CH₂O
Finally, we shall determine the molecular formula. Details below:
Molar mass of compound = 180 g/molEmpirical formula = CH₂OMolecular formula =?Molecular formula = empirical × n = mass number
[CH₂O]n = 180
[12 + (2×1) + 16]n = 180
30n = 180
Divide both sides by 30
n = 180 / 30
n = 6
Molecular formula = [CH₂O]n
Molecular formula = [CH₂O]₆
Molecular formula = C₆H₁₂O₆
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Need help ASAP 100 points!
How many molecules are in 2.3 moles of Oxygen?
Question 1 options:
2.06 x 1023 molecules
6.02 x 1023 molecules
1.4 x 1023 molecules
3.8 x 1023 molecules
1.4 x 1023 molecules are present in 2.3 moles of oxygen.
How many molecules will be in the 2.3 moles of oxygen?We know that if we multiply the 2.3 moles of oxygen with Avogadro's number which is 6.023 x 1023 then this will give us the number of molecules which is present in the 2.3 moles of oxygen and which is 13.85 x 1023.
Mole is a standard scientific unit for measuring large quantities of very small entities like atoms, molecules, or other specific particles. The mole entitles an extremely large number of units about 6.02214076 × 1023.
So we can conclude that by multiplying Avogadro's number with the 2.3 moles of oxygen then it will give us 1.4 x 1023 molecules.
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The number of gas molecules in a container is doubled. How will the pressure in the container change if the temperature and volume of the container do not change?
Answer:
when De molecules are wide open
Explanation:
due to the molecules gas contains
PLEASE HELP ME ASAP
Which type of muscle is responsible for digestion?
A. smooth muscle
B. tendon muscle
C. skeletal muscle
D. cardiac muscle
Answer:
A
smooth muscle is responsible
In an acid-base titration, a student uses 25.62 mL of 0.100 M HCl to reach the endpoint. How many moles of acid is this?
A)2.56 x 10-1 ml HCl
B)2.56 x 10-3 mol HCl
C)2.56 x 10-2 mol HCl
Answer:
Number of mole in HCL = 2.56 x 10⁻³ mol HCL
Explanation:
Given:
Volume of HCL = 25.62 ml
Molarity of HCL = 0.1 M
Find;
Number of mole in HCL
Computation:
Volume of HCL = 25.62 ml
Volume of HCL (in liter) = 25.62 / 1000
Volume of HCL (in liter) = 0.02562 L
Number of mole = Molarity x volume in liter
Number of mole in HCL = Volume of HCL (in liter) x Molarity of HCL
Number of mole in HCL = 0.02562 x 0.1
Number of mole in HCL = 0.002562
Number of mole in HCL = 2.56 x 10⁻³ mol HCL
Sediments from mountains many miles away are now in the area known as Florida. Which is the best explanation as to how most of these sediments moved so far away from where the mountains are now?
Answer:
The sediments were transported and deposited by streams and rivers.
Explanation:
:)
iupac name for Ag(S2O3)2
Answer:
Dithiosulfatosilver
Explanation:
For the reaction H2(g) +O2(g) — H2O (g) how many liters of water can be made from 5 L of oxygen gas at 37.0 Celsius, 1.76atm and an excess of hydrogen?
Answer:
12.5 L
Explanation:
Part 1 - Finding Number of moles
First thing we need to find out is number of moles of oxygen gas. We can achieve this using the formula: PV=nRT
Pressure (Pa) x Volume (cubic meters) = no. moles x gas constant (8.31 J/K*mol) x Temperature (K)
We can rearrange this formula to solve for no. moles:[tex]n=\frac{PV}{RT}[/tex] and plug in the values to solve.
1 atm = 1.01325 x 10^5 Pa, therefore 1.76atm = [tex]1.76*1.01325*10^{5} =178332Pa[/tex]
1 L = 1 x 10^-3 m^3, therefore 5L = [tex]5*1*10^{-3}=5*10^{-3}m^{3}[/tex]
Finally Kelvin = Celsius + 273.15, therefore 37.0C = [tex]37.0+273.15=310.15K[/tex]
Substituting this all back into the formula we get:
[tex]n=\frac{(178332)(5*10^{-3})}{(8.31)(310.15)}[/tex]
[tex]n=\frac{891.66}{2577.3465}[/tex]
[tex]n=0.346[/tex] moles (3.s.f)
Part 2 - Balancing Equation
The equation given is not balanced so we need to balance it to find the correct molar ratio. We can start by balancing the oxygens as there are less of them. We can see that there are 2 oxygen atoms on the left as denoted by 'O2' but only one on the right in 'H2O', therefore we can add a two in front of the H2O on the right side to balance the oxygen atoms:
[tex]H_{2(g)} +O_{2(g)} - > 2H_{2} O_{(g)}[/tex]
Now we have four hydrogens on the right side so we have a 2 in front of H2 on the left hand side to balance the hydrogens:
[tex]2H_{2(g)} +O_{2(g)} - > 2H_{2} O_{(g)}[/tex]
And voila! The equation is balanced and shows the correct molar ratio.
Part 3 - Calculating moles of water
As we can see from the molar ratio in the balanced equation, every mole of O2 will produce two moles of H2O- the ratio is 1:2. As we have an excess of hydrogen, we only need to worry about the amount of oxygen we have. Therefore to calculate the number of moles of water that can be made we simply need to multiple by the ratio:
[tex]0.346*2=0.692[/tex] moles of water
Part 4 - Converting to Liters
Finally, to convert our amount of moles into volume, we can use water's molecular mass to find the mass and then its density to find its volume. Water's molecular mass is 18.02gmol^-1 (2x1.01+16.00) and its density is 997kg/m^3.
m=nM (mass = no. moles x molecular mass): m=[tex]0.692*18.02=12.46984g[/tex]
rho = m/v (density = mass/volume): [tex]997=12.46984/v[/tex], therefore [tex]v=0.0125m^{3}[/tex]
Finally as mentioned above, 1 L = 1 x 10^-3 m^3, therefore the volume of water that can be made is 12.5 Liters.
How can people REDUCE the amount of trash being put into landfills?
A recycle paper, glass, plastic and metal
B reuse shopping bags and food containers
compost biodegradable materials
D
all of the above
A scientist did a test to compare two substances: substance Q and substance R. At room temperature, both substances are liquid. When the scientist transferred the same amount of energy out of both substances, only one substance changed phase while the other did not. Which substance changed phase, and how did it change?
Responses
a
Substance Q changed phase because the attraction of the molecules was able to overcome their slower movement. Its molecules now move in place.
Substance Q changed phase because the attraction of the molecules was able to overcome their slower movement. Its molecules now move in place.
b
Substance Q changed phase because the strong attraction between molecules made their movement slower. Its molecules now move in place.
Substance Q changed phase because the strong attraction between molecules made their movement slower. Its molecules now move in place.
c
Substance R changed phase because the weak attraction between molecules let them move faster. Its molecules now move around each other.
Substance R changed phase because the weak attraction between molecules let them move faster. Its molecules now move around each other.
d
Substance R changed phase because the attraction was able to overcome the slower molecules. Its molecules now move away from each other.
Substance R changed phase because the attraction was able to overcome the slower molecules. Its molecules now move away from each other.
Substance R changed phase because the weak attraction between molecules let them move faster. Option C
What is phase change?We know that a change of phase has to do with the movement of a material from a given state of matter to the other. Net us note that when there is a change of state, we are going to notice that the force of attraction in the molecule would also change.
Since we know that the substance that we have are liquid at room temperature, we know that the supply of some energy may cause to be bale to change its phase.
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Last year Steve was shorter than his brother. This year Steve is taller than his brother. What cell process is directly responsible for Steve’s growth?
1 diffusion
2 mitosis
3. Osmosis
4 respiration
Answer:
he drank milk!!!
Explanation:
1. he told his dad to go get the milk
2. Steve's dad didn't come back until a year!
3. Steve's dad came back and gave him milk!
4. and boom, he grew!!
:)
All living organisms are capable of growing and producing offspring. All eukaryotic organisms including aquatic plants and algae grow through mitosis. Thus the correct option is 2.
What is mitosis?The mitosis is defined as the step in the cell cycle where the newly formed DNA is separated and results in the formation of two new cells which have the same number and kind of chromosomes as the parent nucleus.
It is defined as a process of asexual reproduction observed in unicellular organisms. The cell division is regarded as the driving process of reproduction at the cellular level. Mitosis is required for the growth of the cells and for the replacement of worn-out cells.
Mitosis helps organisms to grow in size and repair damaged tissue. The process of mitosis generates new cells which are genetically identical to each other.
Thus the correct option is 2.
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The mass of copper nitrate produced from reacting 3.65g of copper and 5.16g of nitric acid
The mass of copper nitrate produced in the reaction 3.65g of copper and 5.16g of nitric acid is 3.84g.
What gas is produced when copper combines with nitric acid?Nitric acid reacts with copper
4 HNO3(l) + Cu(s) ==> Cu(NO3)2(s and aq) + 2 NO2(g) + 2 H2O(l)
Deep blue colour characterises the copper nitrate salt that develops. Nitrogen dioxide is the gas that is created when strong nitric acid and copper interact. This maroon mist is nitrogen dioxide.
Copper :
=> mass copper nitrate
=> 3.65g Cu x 1mol of Cu/63.546 g Cu x 1 mol copper nitrate / 1 mol cu x 187.56 g/mol copper nitrate
=> 10.77g
HNO3 (Nitric acid):
=> Mass copper nitrate =3.65 g HNO3 X 1 mol HNO3/63.546 g HNO3 x 1mol of copper nitrate /4 mol HNO3 x 187.56 g/mol copper nitrate.
=> 3.84g.
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Lewis Structure Practice (No Links Or I will Report)
Answer:
.. ..
:O = C - Cl:
.. | ..
:Cl:
..
Half equations for oxidation of HCL
The glycerol-3-phosphate shuttle can transport cytosolic NADH equivalents into the mitochondrial matrix (see Fig. 15.11c). In this shuttle, the protons and electrons are donated to FAD, which is reduced to FADH2. These protons and electrons are subsequently donated to coenzyme Q in the electron transport chain. Given that the number of ATP molecules made per NADH and FADH2 oxidation differ by ____? the amount of ATP generated per mole of glucose when the glycerol-3-phosphate shuttle would be ____ instead of 32.
Answer:
The number of ATP molecules made per NADH and FADH2 oxidation differ by 1.
The amount of ATP generated per mole of glucose when the glycerol-3-phosphate shuttle would be 30 instead of 32.
Explanation:
The glycerol-3-phosphate shuttle can transport cytosolic NADH equivalents into the mitochondrial matrix. In this shuttle, the protons and electrons are donated to FAD, which is reduced to FADH2. These protons and electrons are subsequently donated to coenzyme Q in the electron transport chain. Given that the number of ATP molecules made per NADH and FADH2 oxidation differ by 1, the amount of ATP generated per mole of glucose when the glycerol-3-phosphate shuttle would be 30 instead of 32.
FADH2 generates 1.5 ATP per molecule unlike NADH which generates 2.5 ATP per molecule. This is because electron transfer via FADH2 is not coupled to proton pumping unlike electron transfer reactions involving NADH. Thus, two moles of NADH from the oxidation of 2 moles of glyceraldehyde-2-phosophate to two moles of 1,3-bisphosphoglycerate will yield 3 moles of ATP rather than 5 moles when shuttled through the glycerol-3-phosphate shuttle. The glycerol-3-phosphate shuttle of cytosolic NADH shuttling occurs mainly in the brain and skeletal muscles and does not involve membrane transporters.
Question (1 point)
Given the model, answer the following questions regarding effusion. The orange spheres have a greater root-mean-square speed than the blue spheres. Assume the balloon has a tiny opening for gas molecules to escape.
1st attempt
Part 1 ( 0.5 point)
See Periodic Table See Hint
Which balloon, A or B, most accurately illustrates the effusion of a gas from the central balloon?
Calculate the relative rate of effusion for the orange to blue spheres. The root-mean-square speed for the orange spheres is 495.0m/s. The root-meah-5quare speed for the blue spheres is 380.0m/ s.
According to the claim, Balloon A, which has more blue and less orange, exhibits accurate effusion at a relative effusion rate of 1.303. (orange is 1.303 times more effused than blue).Relative rate of effusion for the orange to blue spheres = 1.531.
What is effusion ?The process of effusion is when a gas escapes from a container through a hole that is significantly smaller in diameter than the molecules' mean free path.
Gas molecules flow through a small opening in one container and into another by effusion. Graham's law allows rates of effusion to be compared at the same temperature. Diffusion is the random molecular motion-based movement of gas molecules through one or more other types of gas.
Rate of effusion of Orange / Rate of effusion of blue
= [Mblue / Morange]^1/2
Vrms = sqrt [(3RT/M)]
Vorange / Vblue = [ Mblue / Morange]^1/2
Rate of effusion of Orange / Rate of effusion of blue
= 565/ 369
= 1.531
Thus, Balloon A, which has more blue and less orange, exhibits accurate effusion at a relative effusion rate of 1.303.
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The volume of a fixed amount of gas is doubled, and the absolute temperature is doubled. According to the ideal gas law, how has the pressure of the gas changed? A. It has stayed the same. B. It has decreased to one-half its original value. C. It has increased to four times its original value. D. It has increased to two times its original value.
Answer:
Option A. It has stayed the same.
Explanation:
To answer the question given above, we assumed:
Initial volume (V₁) = V
Initial temperature (T₁) = T
Initial pressure (P₁) = P
From the question given above, the following data were:
Final volume (V₂) = 2V
Final temperature (T₂) = 2T
Final pressure (P₂) =?
The final pressure of the gas can be obtained as follow:
P₁V₁/T₁ = P₂V₂/T₂
PV/T = P₂ × 2V / 2T
Cross multiply
P₂ × 2V × T = PV × 2T
Divide both side by 2V × T
P₂ = PV × 2T / 2V × T
P₂ = P
Thus, the final pressure is the same as the initial pressure.
Option A gives the correct answer to the question.
What is a molecule of compound made up of?
A one type of atoms
B two or more of the same type of atoms
C two or more of different types of atoms
D two or more of the same type or different types of atoms
[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]
D. Two or more of the same type or different types of atoms.
ThanksHope it helps.Propane is used as a fuel for camp stoves. It undergoes combustion to form carbon dioxide and water.
C3H8 +502 – 3 CO2 + 4H20
Determine the number of molecules of propane needed to produce 10.01 liters of carbon dioxide.
CORRECT ANSWER IS: 8.97 x 10^22 molecules C3H8, but what are the steps to get this answer?
Charged Particles
Charge on Particle Number of Particles
Positive 3
Negative 2
A negatively charged substance is brought near the ion. What will most likely happen?
(A) The negatively charged ion will repel the substance.
(B) The negatively charged ion will attract the substance.
(C) The positively charged ion will repel the substance.
(D) The positively charged ion will attract the substance.
Answer:
D
Explanation:
cause overall charge is +1 so will attract
Which among the following is NOT TRUE regarding solutions?
A.
a solution is a homogeneous mixture of two or more components
B.
in a liquid solution the solution particles can be ions, atoms or molecules and never settle on standing
C.
the solution particle size is much smaller than colloidal particle.
D.
solution particles can be separated by filtration.
E.
air is a gaseous solution of gases, chiefly oxygen and nitrogen.
Answer:
The answer is D.
Explanation:
I know because I am currently doing this topic in Chemistry as well. I hope it was enough.
name one solid that can be used in place of candle wax while will give the same result
Answer:
Paraffin Wax
Explanation:
Paraffin wax is one of the most widely used waxes for candle making. A cheaper alternative, it is a derivable from petroleum, coal or oil. This wax is white and odorless and will keep a consistent appearance throughout your candle's life.
Half equations for oxidation of HCL
Explanation:
The other half of the equation involves the hydrogen ions (initially bonded to the chloride ion in the hydrochloric acid). The hydrogen ions gain the electrons lost by the zinc atom, and bond together to form hydrogen gas. Since the hydrogen ions gain electrons, it is a reduction reaction.
1. what are the methods of vegetative propagation
2.give examples of organisms exihibiting each type
3.tubers-definitio example potatoes
science subject
Natural vegetative propagation uses bulbils, aerial shoots, roots, underground stems, and subaerial stems. Utilizing unique vegetative components, artificial vegetative propagation is accomplished.
What is vegetative propagation, and how does it work?The production and growth of a new plant through asexual means or from a plant fragment is known as vegetative propagation. There is no gamete production or fertilization throughout the process of propagation.
What are some instances of vegetative tuber propagation?In this procedure, tubers—modified roots—grow into new plants. In some plant species, adventitious buds even grow on the roots. If the correct circumstances are present, these buds develop into new plants or sprouts. Sweet potato and dahlia are two examples.
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Carrying capacity is
A
anything that limits how many organisms can live in an ecosystem.
B
how green plants make carbohydrates.
С
the process of respiration.
D
the number of organisms an ecosystem can support.
Answer:
It's D the number of organisms an ecosystem can support.
Check if it's right first then if it is, happy to help
Answer:
D: The number of organisms an ecosystem can support
Explanation:
D is the correct answer.
Please solve this fast pleasee i will make u the brainliest
I – FILL IN THE BLANKS:-
1. _____________plastics can be melted by heating and thereafter moulded into desired
shape.
2. Melamine and Bakelite are examples of____________________________.
3. _________________ absorbs sweat.
4. ______________are used for making toothbrush bristles.
5. _____________type of plastic is used for making grocery bags.
6. _____________type of plastic is used for making microwave cooking containers.
7. __________ fibres are obtained from plant and animals.
8. Synthetic fibres are acquired from __________ products.
9. Polythene is the polymer of __________.
10. __________ was the first artificially manufactured fibre.
11. Polyesters are extremely __________ and __________.
12. __________ is used as an alternative for expensive, warm cashmere clothes.
13. The polymer cellulose is made up of a large number of __________ units.
14. Silk fibre is obtained from __________ whereas artificial silk is obtained by chemical
treatment of __________
15. Polythene which is used to make polythene bags is an example of a __________.
16. Plastics do not react with _______________ and ____________________.
17. Plastics are generally ______________-____ than metals.
18. __________ is a special plastic on which oil and water do not stick.
19. We should always remember the 5R principle: __________, __________, __________,