Answer:
any 5 ways to prevent earth are:
1.using ( 3R) principles Reduce, reuse, and recycle.
2.Educate yourself
3.Conserve water resources and other natural resources
4.Use long-lasting light bulbs.
5.stop deforestation and start afforestaion
Nung hoàn toàn 173,8g Kali pemanganat để điều chế khí oxi. a/ Tính thể tích khí oxi thu được (đktc). b/ Đốt 12,4g photpho trong lọ chứa khí oxi trên. Sau khi phản ứng kết thúc đưa que đóm còn tàn đỏ vào ống nghiệm thì que đóm có bùng cháy không? Vì sao
Answer:
45
Explanation:
because the number is right
The most common carrier of communicable diseases are
a.cockroach
b.housefly
c.mosquito
d.spider
housefly
Explanation:
Because it one of the affective vector of disease carrier and it always roam towards wastes and dirty materials likely to get attracted . And it carries contagious disease from hospitals , infected patients , etc .
Tyndall effect example (any 2)
Answer:
1. Sunlight path becoming visible when lots of dust particles are suspended in the air such as light passing through the canopy of a dense forest.
2.When a torch is switched on in a foggy environment, the path of the light becomes visible.
What are the example of molecule ?
Explanation:
H2O water molecule
O3 Ozone
are some of common example of molecules
Give structural formula of ethylene. What type of bond is found in between carbon and hydrogen? Why is the bond between carbon and carbon weak in it?
Answer:
See explanation
Explanation:
The structure of ethylene is shown in the image attached. The two carbon atoms have a double covalent bond between them.
The two carbon atoms are sp2 hybridized. The bond between them is a covalent bond, there is one pi bond and one sigma bond between the carbon atoms. Between carbon and hydrogen, there are covalent bonds also. The covalent bonds are sigma bonds.
The pi bonds between carbon atoms is weaker than the sigma bonds between the carbon atoms. This is because, the side-by-side overlap the p orbitals in a pi bond is less effective than the end-to-end overlap of a sigma bond.
What is the general function of enzymes in the human body?
O A. They make fatty acids unsaturated.
OB. They speed up chemical reactions.
O C. They store genetic information.
D. They carry instructions for making proteins.
Answer:
C
they store genetic information
B. They speed up chemical reactions
Vector quantity has magnitude but no direction
Answer:
False
Explanation:
it has both magnitude and direction and unit
Diego is trying to lift a piano to the second floor of his house. Diego uses a pulley system and gives a big lift to the piano.The piano moves upward, then stops, and then it starts to fall to the ground. (The direction of the force of gravity is negative.) Which list best describes the forces on the piano in the proper order
Answer:
positive force → balanced force → negative force
Explanation:
np
Answer:
positive force → balanced force → negative force
Explanation:
:)))
PLS HELP ASAPPP!!!
Compare and contrast an electrolytic cell with a voltaic cell. Provide one example where both are present in daily life.
Voltaic cells convert chemical energy to electrical energy by means of an oxidation-reduction reaction while Electrolytic cells convert electrical energy to chemical energy, so they are the opposite of voltaic cells,in an electrolytic cell, the cathode is negatively charged and the anode is positively charged
Answer:
ELECTROLYTIC CELL
An electrochemical cell in which a non-spontaneous chemical reaction takes place when electric current is passed through the solution,is called an electrolytic cell.
EXAMPLE
Nelsons cell and Downs cell
VOLTAIC CELL OR GALVANIC CELL
The electrochemical cell in which a spontaneous chemical reaction takes place and generates electric current is called galvanic and voltaic cell.
EXAMPLE
Daniel cell
Explanation:
The general shape that an electron is located within an energy level_____
Answer:
Concentric circles
Explanation:
The energy levels are shown as concentric circles around the central nucleus, and the electrons are placed from the inside out. The first two electrons are found in the first energy level, and the third electron is found in the second energy level.
State whether the following statement is true or false. If false, then rewrite
1. Melting of ice is a physical change.
Answer:
True
Explanation:
A physical change is a change of state. So when ice melts it changes from a solid to a liquid so it is a physical change
Calculate the average atomic mass for element X
Answer:
51.6058
Explanation:
The percentage of abundance is changed to decimal by dividing 100
what is one cause of long-lasting climate change?
Answer: Carbon dioxide is the main cause of human-induced climate change. ... Some, such as nitrous oxide, are long-lived greenhouse gases like carbon dioxide, and so contribute to long-term climate change. Other substances have shorter atmospheric lifetimes because they are removed fairly quickly from the atmosphere.
hope it helps
An atom has9 electrons and 9 protons at the start. If it loses 2 electrons, what would the net charge on the atom be
Answer:
i hope it will help you
Explanation:
there will be 7 electrons and 9 protons will have 2+ charge.
What is the frequency of a wave that has a wavelength of 28 m? c = λυ where c = 2.998 x 108 m/s
a. 1.07 x 107 Hz
b. 2.3 x 107 Hz
c. 10 Hz
d. 10.7 Hz
Answer:
The frequency of a wave that has a wavelength of 28 m is 1.07*10⁷ Hz.
Explanation:
Wavelength is the minimum distance between two successive points on the wave that are in the same state of vibration. It is expressed in units of length (m).
Frequency is the number of vibrations that occur in a unit of time. Its unit is s⁻¹ or hertz (Hz).
The propagation speed is the speed with which the wave propagates in the medium, that is, it is the magnitude that measures the speed at which the wave's disturbance propagates along its displacement. Relate the wavelength (λ) and the frequency (f) inversely proportional using the following equation:
v = f * λ.
Being:
v= 2.998*10⁸ m/sf= ?λ= 28 mReplacing:
2.998*10⁸ m/s= f* 28 m
Solving:
[tex]f=\frac{2.998*10^{8}m/s }{28m}[/tex]
f= 1.07*10⁷ Hz
The frequency of a wave that has a wavelength of 28 m is 1.07*10⁷ Hz.
How many ATOMS of boron are present in 3.61 grams of boron trifluoride ?
Hi there!
[tex]\large\boxed{3.203 * 10^{22} atoms}[/tex]
We can use the following conversions to solve:
Total mass --> amount of mols --> amount of atoms (Avogadro's number)
Begin by calculating the amount of boron trifluoride in 3.61 grams:
3.61 g * (1 mol BF₃ / 67.8 g) ≈ 0.0532 mol BF₃
Use avogadro's number to convert:
0.0532 mol * 6.02× 10²³atoms / 1 mol = 3.203 × 10²² atoms
A hot metal plate at 150°C has been placed in air at room temperature. Which event would most likely take place over the next few minutes? Molecules in both the metal and the surrounding air will start moving at lower speeds. Molecules in both the metal and the surrounding air will start moving at higher speeds. The air molecules that are surrounding the metal will slow down, and the molecules in the metal will speed up. The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down. Mark this and return
What is the specific latent heat of fusion for a substance that takes 550 kJ to melt 14 kg at 262 K?
A. 3.9 x 10^4 J kg-1
B. 39.29 J kg-1
C. 29.39 J kg-1
D. 1.99 J kg-1
Answer:
The answer is A
Explanation:
hope it helps
(Please help)
What is the most common isotope for element X
Answer:
Isotope 2
Explanation:
Isotope 2 is the most abundant. Its percent abundance is 78.68% which is the largest percentage, and therefore the most common of the isotopes presented.
Good luck!
according to the article, which of the following may be affected by a scientists bias?
ayuda, ayuda, ayuda urgente tengo 5 minutos necesito el nombre de lo que viene en las imágenes
Answer:huh
Explanation:
calculate the final pressure of a gas that is expanded from 725cm³ at 30C and 1.19 atm to 1.12cm³ at 43C
Answer:
Final pressure, P2 = 1088.89 atm
Explanation:
Given the following data;
Initial volume, V1 = 725 cm³Initial temperature, T1 = 30°CInitial pressure, P1 = 1.19 atmFinal volume, V2 = 1.12 cm³Final temperature, T2 = 43°CTo find the final pressure (P2), we would use the combined gas law.
Mathematically, the combined gas law is given by the formula;
[tex] \frac {PV}{T} = k [/tex]
[tex] \frac {P_{1}V_{1}}{T_{1}} = \frac {P_{2}V_{2}}{T_{2}} [/tex]
Substituting into the formula, we have;
[tex] \frac {1.19*715}{30} = \frac {P_{2}*1.12}{43} [/tex]
[tex] \frac {850.85}{30} = \frac {P_{2}*1.12}{43} [/tex]
[tex] 28.3617 = \frac {P_{2}*1.12}{43} [/tex]
Cross-multiplying, we have;
[tex] 28.3617 * 43 = 1.12P_{2} [/tex]
[tex] 1219.5531 = 1.12P_{2} [/tex]
[tex] P_{2} = \frac {1219.5531}{1.12} [/tex]
Final pressure, P2 = 1088.89 atm
Please a little help in this I will really appreciate it
Answer:
b is your answer...........
What are the steps for writing the formula for an ionic compound? Naming an ionic compound?
Answer:
i hope it will help you
Explanation:
To find the formula of an ionic compound, first identify the cation and write down its symbol and charge. Then, identify the anion and write down its symbol and charge. Finally, combine the two ions to form an electrically neutral compound.
Kelvin And Mimi studied the fruits. Kelvin concluded that there are more ovules in a mango flower than a papaya flower while Mimi
argued that there are more ovules in a papaya flower than a mango flower.
(a) who is correct?
(b)Explain your answer in (a).
Answer:
kevin is right according to what i see
3) The spectrum of the unknown mixture is a mixture of two substances among the five. What are these two substances
Answer:
a. H + d. Na
Explanation:
This is Mixture of H and Na. Because of H and in the emission and Absorption spectrum of H Total 5 lines [Red, Green, Blue and Purple (2)) are present and in the spectrum of Na Two yellow lines are present. In the mixture all this lines are are also 5 + Present. Total lines are 5+2= 7 (H+ Na)
Therefore, the answer is a. H + d. Na
A piece of solid tin is submerged in silver nitrate solution. A reaction occurs producing tin (iv) nitrate solution and solid silver. Write the word equation, write the skeletal equation and balanced chemical equation for the reaction.
Answer: For the given reaction-
The word equation is Tin + silver nitrate = tin (IV) nitrate + silverThe skeletal equation is [tex]Sn + AgNO_{3} \rightarrow N_{4}O_{12}Sn + Ag[/tex]The balanced chemical equation is [tex]Sn(s) + 4AgNO_{3}(aq) \rightarrow N_{4}O_{12}Sn(aq) + 4Ag(s)[/tex]Explanation:
When names of chemicals or species involved in a chemical reaction are represented in the form of an equation then it is known as a word equation.For example, Tin + silver nitrate = tin (IV) nitrate + silver
The 'equal to' symbol denotes a forward arrow.
A skeletal equation contains only the chemical formula of species involved in a chemical reaction.For example, [tex]Sn + AgNO_{3} \rightarrow N_{4}O_{12}Sn + Ag[/tex]
A chemical equation which contains same number of atoms on both reactant and product side along with states of species is called a balanced chemical equation.[tex]Sn(s) + 4AgNO_{3}(aq) \rightarrow N_{4}O_{12}Sn(aq) + 4Ag(s)[/tex]
A substance x has a mass of 0,20g and molecular mass of 40g/mol.Find the number of moles of substance x.
Answer:
0,005
Explanation:
number of moles=mass/molecular mass
therefore it's going to be 0,20g over 40g/mol
which is 0,20g/40g/mol... grams and grams will cancel making the answer 0,005moles
If hydrofluoric acid is a stronger acid than acetic acid, which statement is most likely true?
The conjugate acid of hydrofluoric acid is weaker than that of acetic acid.
The conjugate acid of hydrofluoric acid is stronger than that of acetic acid.
The conjugate base of hydrofluoric acid is weaker than that of acetic acid.
The conjugate base of hydrofluoric acid is stronger than that of acetic acid.
Answer: The statement conjugate base of hydrofluoric acid is weaker than that of acetic acid is most likely true.
Explanation:
A strong acid upon dissociation gives a weak conjugate base. This can also be said as stronger is the acid, weaker will be its conjugate base or vice-versa.
Hydrofluoric acid is a strong base as it dissociates completely when dissolved in water.
For example, [tex]HF \rightleftharpoons H^{+} + F^{-}[/tex]
The conjugate base is [tex]F^{-}[/tex] which is a weak base.
Acetic acid is a weak acid as it dissociates partially when dissolved in water. So, the conjugate base of acetic acid is a strong base.
[tex]CH_{3}COOH \rightarrow CH_{3}COO^{-} + H^{+}[/tex]
Thus, we can conclude that the statement conjugate base of hydrofluoric acid is weaker than that of acetic acid is most likely true.
What element has 9 electrons, and 11 neutrons?
fluorineelement has 9 electrons, and 11 neutrons
